阅读说明：本技术 绝对位置检测装置和方法以及存储介质 (Absolute position detection apparatus and method, and storage medium ) 是由 野口和宏 于 2019-08-22 设计创作，主要内容包括：本公开涉及绝对位置检测装置和方法以及存储介质。绝对位置检测装置包括计算器,该计算器被配置为基于检测信号生成第一信号和第二信号。刻度和传感器的相对移动范围包括第一信号中的相邻检测单位之间的边界,使得边界中的至少一个被包括在相对移动范围内的多个区域中的每个区域中。计算器被配置为基于所述多个区域中的包括边界的区域中的第二信号的每个检测单位的代码,指定第一信号中的要用于计算绝对位置的检测单位。(The present disclosure relates to an absolute position detection apparatus and method, and a storage medium. The absolute position detecting device includes a calculator configured to generate a first signal and a second signal based on the detection signal. The relative movement range of the scale and the sensor includes boundaries between adjacent detection units in the first signal such that at least one of the boundaries is included in each of a plurality of regions within the relative movement range. The calculator is configured to specify a detection unit to be used for calculating the absolute position in the first signal based on the code of each detection unit of the second signal in an area including the boundary among the plurality of areas.)

1. An absolute position detecting device, comprising:

a scale having a periodic pattern;

a sensor configured to output a detection signal corresponding to the periodic pattern according to a relative movement between the scale and the sensor; and

a calculator configured to generate, based on the detection signal, a first signal having a detection unit that is a first relative movement amount between the scale and the sensor and a second signal having a detection unit that is a second relative movement amount between the scale and the sensor, the second relative movement amount being smaller than the first relative movement amount, and obtain an absolute position based on the first signal and the second signal,

wherein the relative movement range of the scale and the sensor includes boundaries between adjacent detection units in the first signal such that at least one boundary is included in each of a plurality of regions within the relative movement range,

wherein the calculator is configured to specify a detection unit to be used for calculating the absolute position in the first signal based on the code of each detection unit of the second signal in an area including the boundary among the plurality of areas.

2. The absolute position detecting apparatus according to claim 1, wherein each of the plurality of areas is shorter than a detection unit of the first signal in a direction of the relative movement.

3. The absolute position detecting apparatus according to claim 1, wherein the calculator is configured to specify the detection unit in the first signal based on a comparison of the code with a predetermined code.

4. The absolute position detecting apparatus according to claim 1, further comprising at least one detecting device configured to output a division signal to divide a relative movement range into the plurality of regions.

5. An apparatus, characterized in that the apparatus comprises:

the absolute position detection apparatus according to any one of claims 1 to 4; and

a movable member, an absolute position of which is detected by absolute position detecting means.

6. An absolute position detection method using a scale having a periodic pattern and a sensor configured to output a detection signal corresponding to the periodic pattern in accordance with a relative movement between the scale and the sensor, the absolute position detection method comprising the steps of:

generating a first signal having a detection unit as a first relative movement amount between the scale and the sensor and a second signal having a detection unit as a second relative movement amount between the scale and the sensor, which is smaller than the first relative movement amount, based on the detection signals; and

an absolute position is obtained based on the first signal and the second signal,

wherein the relative movement range of the scale and the sensor includes boundaries between adjacent detection units in the first signal such that at least one boundary is included in each of a plurality of regions within the relative movement range,

wherein the obtaining step specifies a detection unit to be used for calculating the absolute position in the first signal based on a code of each detection unit of the second signal in an area including the boundary among the plurality of areas.

7. A non-transitory computer-readable storage medium characterized by storing a computer program for causing a computer to execute the absolute position detection method as defined in claim 6.

Technical Field

The invention relates to an absolute position detection apparatus and method, and a storage medium.

Background

One of the absolute type position detecting devices described above is disclosed in japanese patent application laid-open No. (JP) 05-26658. The position detecting apparatus reads two magnetic scales having slightly different pitches λ a and λ b by a magnetic sensor, and generates an absolute position signal varying in a pitch λ c such as a sawtooth wave shape using a phase difference between the obtained two phase signals. In addition, by making the origin points coincide with each other and by specifying the number of points from which each waveform portion is distant from the origin point, it reads gray code as an optical scale at a pitch λ c for magnetic scale by an optical sensor.

JP2013-234861 discloses another position detection device. The position detecting device has slightly different long periods P by alternately arranging on two scale tracks₁And P₁Periodic pattern of' and with slightly different short periods P₂And P₂The periodic pattern of' to spatially multiplex. The sensor reads these periodic patterns in a time-division manner. It is based on having a long period P₁And P₁The periodic pattern of 'generates a cursor signal Sv1(═ Φ 1- Φ 1'), and has a short period P according to the pattern₂And P₂The periodic pattern of 'generates a cursor signal Sv2(═ 2-2'). By synchronizing Sv1 and Sv2 with each other, the absolute position is detected with the accuracy of Sv 2.

However, the position detecting device disclosed in JP 05-26658 cannot specify the number of each waveform portion accurately, and the boundary between two adjacent waveform portions in the absolute position signal is shifted from the boundary between the optical scales. In addition, as the movable range of the movable member becomes wider, the number of bits of gray code needs to be increased, which may be disadvantageous from the aspect of space saving.

The position detection apparatus disclosed in JP2013-234861 generates a vernier signal using two periodic patterns having slightly different pitches, and therefore the amount of movement of a movable member for detecting an absolute position is limited due to periodic pattern shape accuracy, pitch error, and the like that can be practically achieved in the manufacturing process.

Disclosure of Invention

For example, it is an aspect of the embodiments to provide an absolute position detecting device that is advantageous in terms of its absolute position detection length.

An absolute position detecting apparatus according to an aspect of the present invention includes: a scale having a periodic pattern; a sensor configured to output a detection signal corresponding to the periodic pattern according to a relative movement between the scale and the sensor; and a calculator configured to generate, based on the detection signals, a first signal having a detection unit that is a first amount of relative movement between the scale and the sensor, and a second signal having a detection unit that is a second amount of relative movement between the scale and the sensor that is smaller than the first amount of relative movement, and to obtain an absolute position based on the first signal and the second signal. The relative movement range of the scale and the sensor includes boundaries between adjacent detection units in the first signal such that at least one of the boundaries is included in each of a plurality of regions within the relative movement range. The calculator is configured to specify a detection unit to be used for calculating the absolute position in the first signal based on the code of each detection unit of the second signal in an area including the boundary among the plurality of areas. An apparatus having the absolute position detecting apparatus, an absolute position detecting method corresponding to the absolute position detecting apparatus, and a non-transitory computer-readable storage medium storing a program enabling a computer to execute the absolute position detecting method also constitute another aspect of the present invention.

Further features of the invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.

Drawings

Fig. 1 shows a reflective scale and a sensor of a position detecting device according to a first embodiment of the present invention.

Fig. 2 shows a periodic pattern on a reflective scale.

Fig. 3A to 3C illustrate phase difference signals according to the first embodiment.

Fig. 4A to 4C illustrate synchronization calculation according to the first embodiment.

Fig. 5A to 5D illustrate a detection unit according to the first embodiment.

Fig. 6 shows a configuration of a position detection apparatus according to the first embodiment.

Fig. 7A and 7B are perspective views of a position detection device according to the first embodiment.

Fig. 8 illustrates the division of the determination area according to the first embodiment.

Fig. 9 illustrates absolute position calculation according to the first embodiment.

Fig. 10 is a flowchart of absolute position calculation processing according to the first embodiment.

Fig. 11 illustrates absolute position calculation according to a second embodiment of the present invention.

Fig. 12 is a flowchart of absolute position calculation processing according to the second embodiment.

Fig. 13A and 13B show the configuration of a position detection apparatus according to a third embodiment of the present invention.

Fig. 14 illustrates absolute position calculation according to the third embodiment.

Fig. 15 is a flowchart of absolute position calculation processing according to the third embodiment.

Fig. 16A and 16B are perspective views of the configuration of a position detection device according to a fourth embodiment of the present invention.

Fig. 17 illustrates absolute position calculation according to the fourth embodiment.

Fig. 18 is a flowchart of absolute position calculation processing according to the fourth embodiment.

Detailed Description

Referring now to the drawings, a description will be given of an embodiment according to the present invention.

First embodiment

Fig. 1 shows a reflective scale (scale having a periodic pattern) 1 and a sensor head (sensor configured to output a detection signal corresponding to the periodic pattern: hereinafter simply referred to as sensor) constituting a position detection apparatus according to a first embodiment of the present invention. In the figure, X, Y and Z denote three directions orthogonal to each other. The sensor 2 includes an LED 3 as a light emitting element and two light receiving ICs 4 and 5. The light receiving ICs 4 and 5 have light receiving element arrays 4a and 5a, respectively, and the light receiving element arrays 4a and 5a include a plurality of light receiving elements arranged at predetermined pitches in the X direction as the relative movement direction (position detection direction) of the reflective scale 1 and the sensor 2. The LED 3 and the light receiving ICs 4 and 5 are mounted on a base substrate 6 and covered with a cover glass 7. A transparent resin 8 is filled in the sensor 2 (between the base substrate 6 and the cover glass 7). The reflective scale 1 and the sensor 2 are disposed to face each other. The light beam emitted from the LED 3 is reflected by the reflective scale 1 and enters the light receiving element arrays 4a and 5 a.

Fig. 2 shows a detail of the reflective scale 1. Directions X, Y and Z in this figure are the same as directions X, Y and Z shown in fig. 1. The reflective scale 1 has a main track 1a and a sub-track 1 b. The main track 1a comprises a track having a short period or pitch P₁Periodic pattern of(hereinafter referred to as a first short-period pattern) 101a and a pattern having a long period or period Q₁The periodic patterns 101a and 101b each extending in the X direction (hereinafter referred to as first long periodic pattern) 101b, Q₁Is a pitch P₁Is four times as long. In the Y direction, the first short periodic patterns 101a and the first long periodic patterns 101b are alternately arranged.

The sub-track 1b comprises a track having a short period or pitch P₂And a periodic pattern (hereinafter referred to as a second short periodic pattern) 102a having a long period or pitch Q₂And a periodic pattern (hereinafter referred to as a second long periodic pattern) 102b, the periodic patterns 102a and 102b each extending in the X direction at a pitch P₂Specific pitch P₁Slightly longer, at a distance Q₂Specific distance Q₁Slightly longer. In the Y direction, the second short periodic patterns 102a and the second long periodic patterns 102b are alternately arranged.

The black part of each periodic pattern in the figure is a reflective part that regularly reflects the light beam from the LED 3, and the white part is a non-reflective part that does not reflect the light beam. The isochrones shown in the figures are pattern reference lines in which the starting positions of the respective patterns coincide with each other. The pitches P of the first short periodic pattern 101a, the first long periodic pattern 101b, the second short periodic pattern 102a, and the second long periodic pattern 102b will be described in detail later₁、Q₁、P₂And Q₂The relationship between them.

Fig. 3A to 3C illustrate the phase difference signal, and a method of generating the phase difference signal will be described. Fig. 3A shows a representative example of signals output from the light-receiving ICs 4 and 5 when the periodic pattern is moved over the light-receiving element arrays 4a and 5 a. The abscissa axis of the graph indicates the length in the detection direction. Five periods of sine wave signals of 90 ° phase difference shown in solid and broken lines are shown as an example.

Fig. 3B shows a repetitive phase signal of 0 ° to 360 ° generated by arctangent conversion of sine wave signals of a phase difference of 90 °. The graph abscissa axis is the same in the three graphs. The solid line 9 represents the phase signal of five cycles (five waves) shown in fig. 3A, and the broken line 10 represents the phase signal of four cycles (four waves) of the same detection length. In other words, they are phase signals obtained from respective periodic patterns in which five periodic patterns and four periodic patterns are arranged with the same length in the detection direction.

Fig. 3C is a graph of a phase difference signal obtained by subtracting the phase signal 10 from the phase signal 9. The abscissa axis represents a position in the position detection direction, and the ordinate axis represents a phase. The solid line 11a is a phase difference signal obtained by subtracting the phase signal 10 from the phase signal 9, and when the amplitude relationship is inverted, it becomes a negative phase value. The broken line 11b is a signal obtained by adding 360 ° when the phase difference signal of the solid line 11a is negative. The process may generate a continuous phase difference signal of 0 ° to 360 °. Therefore, it can be seen that when the difference in the number of periodic patterns in the same detection length is "1", one continuous phase difference signal is generated in the range of 0 ° to 360 °.

Fig. 4A to 4C illustrate the synchronization calculation, and a description will be given of a procedure for finally determining an absolute position from one phase difference signal associated with an arbitrary position of the repetitive phase signal 9. Fig. 4A is a graph of the phase signal 9 shown by a solid line and the phase difference signal 11b shown by a broken line illustrated in fig. 3A to 3C, in which the axis of abscissa indicates the length in the detection direction and the axis of ordinate indicates the phase, and shows a range of degrees from 0 ° to 360 °. Since five waves of the phase signal 9 are shown and one wave of the phase difference signal 11b is shown, it is clear that the signal slopes differ by five times.

Fig. 4B shows the phase signal 9 and a signal 11B' obtained by multiplying the phase difference signal 11B by 5 in an enlarged display range from 0 ° to 1800 ° (═ 360 ° × 5) of the ordinate axis so that the above-described signal slopes coincide with each other.

Fig. 4C illustrates calculation for determining the number of each wave (code: hereinafter referred to as wave number) of the phase signal 9. Subtracting the phase signal 9 from the signal 11 b' and adding 180 deg. results in a step signal denoted by reference numeral 12. Although the phase signal 9 and the phase difference signal 11B are represented by straight lines, the phase difference signal 11B is a difference signal between the phase signal 9 and the phase signal 10 shown in fig. 3B, and thus contains error components of the two original signals. The signal 11 b' contains a larger error signal because it has been amplified five times. The step signal 12 is not a straight line, and for example, the first signal 12a is a signal including an error range by setting the average value to about 180 ° between 0 ° and 360 °.

When the step signal 12 is divided by 360 ° and only an integer part thereof is extracted, the wave number "N" of each of the five waves in the phase signal 9 is calculated_D"(═ 0 to 4). When the signal including the error is in a state of ± 180 ° or more, a correct wave number cannot be obtained, indicating wave numbers on both sides, and thus correct synchronous calculation cannot be performed.

Referring back to fig. 4A, an arbitrary phase θ of the phase difference signal 11b will be given_UDescription of the location of (a). The phase of the phase signal 9 at this position is θ_DAnd the wave number "N" at that position_D"by the above-described synchronization calculation is expressed as follows.

N_D＝INT{[5×θ_U--θ_D+180]÷360} (1)

According to formula (1), N_DBecomes 2. However, INT () is an integer conversion (integer quantization) that rounds out decimal points. Therefore, the absolute value (absolute position) θ at this position is expressed as follows.

θ＝360×N_D+θ_D(2)

According to equation (2), by comparing the phase θ of the phase signal 9 at the current position_DBy adding two previous phases 360 × 2 of the phase signal 9, accurate detection (calculation) can be obtained using the phase signal 9 as an original signal based on the phase difference signal 11b including a large error of the absolute position θ.

It will be given how to set the pitch P shown in FIG. 2₁、Q₁、P₂And Q₂Description of the periodic pattern of (a). According to this embodiment, on the main rail 1a, 75 pitches Q in the X-axis direction₁And 300 pitches P₁Equally long, each pitch Q₁Is a pitch P₁Is four times as long. On the other hand, on the sub-track 1b, a pitch P is set₂And Q₂So that 290 pitches P₂And 74 spaces Q₂Have the same length. In other words, at pitch P₁、Q₁、P₂And Q₂The following holds.

P₁×300＝Q₁×75＝P₂×290＝Q₂×74

As described for the phase difference signal with reference to fig. 3B and 3C, with a pitch Q₁And Q₂Generating a phase difference signal of 1(═ 75-74) waves and using the pitch P₁And P₂A phase difference signal of 10 (300-.

Fig. 5A to 5D illustrate a detection unit as a unit for detecting an absolute position. FIG. 5A illustrates the use of a spacing Q₁And Q₂A phase difference signal is generated, and FIG. 5B shows the phase difference signal generated with the pitch P₁And P₂Ten phase difference signals are generated. FIG. 5C illustrates the use of a spacing Q₁Seventy-five phase signals are generated, and FIG. 5D shows the use of pitch P₁Resulting in three hundred phase signals.

Assume that the phase value in fig. 5A is θ_WAnd the phase value in fig. 5B is θ_X. Then, the wave number "N" is determined by the calculation of the following formula (3) by the synchronous calculation described in fig. 4A to 4C_X”。

N_X＝INT{[10×θ_W-θ_X+180]÷360} (3)

Assume that the phase value in fig. 5C is θ_Y. Then, theta_XIs 7.5 times, so that the wave number "N" is calculated by the following formula (4)_Y"is determined as [0 to 74 ]]。

N_Y＝INT{[7.5×(360×N_X+θ_X)-θ_Y+180]÷360} (4)

Assume that the phase value in fig. 5D is θ_Z. Then, theta_YIs 4 times, and the wave number "N" is calculated by the following formula (5)_Z"is determined as [0 to 299]。

N_Z＝INT{[4×(360×N_Y+θ_Y)-θ_Z+180]÷360} (5)

Therefore, the phase difference signal θ as the lower signal (the intermediate signal, the lower signal, and the lowermost signal)_XAnd phase signal theta_YAnd theta_ZPhase difference signals θ with one wave as the uppermost signal shown in fig. 5A, respectively_WAnd (4) associating. In each of these signals, a part of the length in the detection direction (relative movement amount) to which each wave number is assigned is one detection unit.

Fig. 6 shows a configuration of a position detection apparatus according to the embodiment. Although the reflective scale 1 and the sensor 2 are shown in fig. 1 as actually facing each other, they are shown side by side in fig. 6. The range sandwiched between the two isocratic lines in the reflective scale 1 is one detection unit (labeled as an absolute position detection unit in fig. 6) described with reference to fig. 5A to 5D. Having a pitch P₁、Q₁、P₂And Q₂Is continuous on both left and right sides.

The microcomputer 20 performs various operations and determinations including the above-described synchronization calculation. The microcomputer 20 outputs a signal "a" from the I/O port 21, and switches the internal circuits of the light-receiving ICs 4 and 5 in a time-division manner. Thereby, the states in which the light receiving element arrays 4a and 4b read the first short-period pattern 101a and the second short-period pattern 102a shown in fig. 2, and the states in which the light receiving element arrays 4a and 4b read the first long-period pattern 101b and the second long-period pattern 102b are alternately switched.

The sensor 2 outputs two signals "b" having a phase difference of 90 °, which corresponds to the pitch P of the first and second short periodic patterns 101a and 102a₁And P₂Or the pitch Q of the first long periodic pattern 101b and the second long periodic pattern 102b₁And Q₂. An a/D converter 22 in the microcomputer 20 a/D converts the signal b. Thereby, a signal as a digital signal is input to the processor 23 in the microcomputer 20.

The light shielding plate 31 is fixed to the movable member and moves integrally with the movable member. When the light-shielding plate 31 enters and leaves the space between the light-emitting portion and the light-receiving portion, the photo interrupters (PI _1 and PI _2)30_1 and 30_2, which constitute the divider together with the light-shielding plate 31, switch the output signal between H and L. Output signals (hereinafter, referred to as division signals) from the photo interrupters 30_1 and 30_2 are input to the processor 23 through the I/O port 21 in the microcomputer 20.

The processor 23 performs inverse tangential transform, phase difference calculation, synchronization calculation, and area determination processing using the input digital signal and the division signal, and outputs the calculation and determination results to the absolute position calculator 24 in the microcomputer 20. The absolute position calculator 24 calculates the absolute position of the movable member using the input calculation and determination results. The processor 23 and the absolute position calculator 24 constitute a calculator.

Fig. 7A and 7B show a specific configuration of the position detecting device for an interchangeable lens or lens barrel of a camera according to this embodiment. The lens barrel has a rotating ring 32 as a movable member that can be rotated by a user. The rotating ring 32 is rotatable about the optical axis within a predetermined rotation range with respect to a fixed cylinder, not shown. The reflective scale 1 is fixed on an inner peripheral portion of the rotating ring 32 and extends in a circumferential direction (position detecting direction). A sensor 2 facing the reflective scale 1 is fixed on an outer peripheral portion of a not-shown fixed cylinder. The position detection means detects the rotational position (absolute position) of the rotating ring 32.

The light shielding plate 31 is integrated with the rotating ring 32. The light shielding plate 31 rotates with the rotation of the rotating ring 32, and moves into and out of a space between the light emitting portion and the light receiving portion of the photo interrupters 30_1 and 30_2 fixed to the fixed cylinder.

Referring now to fig. 8, a description will be given of dividing the absolute position detection range into the relative movement range between the reflective scale 1 and the sensor 2 according to this embodiment. Fig. 8 is an expanded view of the sensor 2 and the photo interrupters 30_1 and 30_2 fixed to the fixed cylinder and the reflective scale 1 and the light shielding plate 31 integrally provided on the rotating ring 32 in the position detection direction in the configuration shown in fig. 7A and 7B. The rotation positions 1 and 4 of the rotating ring 32 represent both end positions of the absolute position detection range. The photo interrupters 30_1 and 30_2 (detection portions) as the detection portions output the division signal H in a light-shielding state where the light shielding plate 31 enters the space between the light emitting portion and the light receiving portion, and output the division signal L in a light-transmitting state where the light shielding plate 31 exits from the space between the light emitting portion and the light receiving portion.

Between the rotational positions 1 and 2, since both the photo interrupters 30_1 and 30_2 are in the light transmitting state, the divided signals output therefrom become L and L, respectively. From the rotational position 2 to the rotational position 3, since the photo interrupter 30_1 is in the light shielding state, the division signals from the photo interrupters 30_1 and 30_2 become H and L, respectively. From the rotational position 3 to the rotational position 4, since the photo interrupter 30_2 is also in the light shielding state, the division signals from the photo interrupters 30_1 and 30_2 become H and H, respectively. Therefore, the absolute position detection range is divided into a plurality of (three in the present embodiment) regions by a combination of the division signals from the photo interrupters 30_1 and 30_ 2. In the following description, each divided region will be referred to as a determination region.

The photo interrupters 30_1 and 30_2 as the detection portion and the light shielding plate 31 as the detected portion are arranged side by side in the rotation direction of the rotating ring 32 as the position detection direction.

Referring now to fig. 9, the calculation of the absolute position according to this embodiment will be described. The upper side in fig. 9 shows the phase difference signal (θ) as the first signal shown in fig. 5A in the absolute position detection range 40_W)41(41a to 41 d). The range in which the phase of the phase difference signal 41 in the position detection direction changes from 0 ° to 360 ° is one detection unit (first relative movement amount) of the phase difference signal 41. In fig. 9, the length of the absolute position detection range 40 is 2.3 times as long as the detection unit of the phase difference signal 41, and there are three boundaries between the detection units (the first wave 41a to the fourth wave 41d) within the absolute position detection range 40. Suppose N_WIs the wave number of the phase difference signal 41. Thus, the wave number of the first wave 41a of the phase difference signal 41 is N_WThe wave number of the second wave 41b is N when equal to 0_WThe wave number of the third wave 41c is N _W2, and the wave number of the fourth wave 41d is N_W＝3。

The phase difference signal (θ) shown in fig. 5B as the second signal is superimposed on the phase difference signal 41_X) Of two adjacent wavesThe boundaries between are indicated by vertical lines. Attached between boundaries or for phase difference signal theta_XIs the phase difference signal θ_XWave number N of_X。

The lower side of fig. 9 shows the position of the light shielding plate 31 (shown in black) moving in the position detecting direction, as well as the reflective scale 1 and the division signal (H or L) from the photo interrupters (PI _1 and PI _2)30_1 and 30_ 2.

This embodiment uses the phase difference signal θ_XThe absolute position is calculated. For each wave, a phase difference signal θ_XChanging its phase from 0 to 360 deg.. The absolute position detection range 40 is divided into three determination regions A, B and C by the light shielding plate 31 and the photo interrupters 30_1 and 30_2, as described with reference to fig. 8. The length in the position detection direction of each determination region is shorter than "one detection unit" of the phase difference signal 41. The determination regions A, B and C each include at most one boundary between two adjacent detection units (waves) in the phase difference signal 41 inside both ends thereof. The determination region a is a region from the rotational position 1 to the rotational position 2 shown in fig. 8, and the determination region B is a region from the rotational position 2 to the rotational position 3. The determination region C is a region from the rotational position 3 to the rotational position 4.

Referring now to the flowchart in fig. 10, a description will be given of absolute position calculation processing (position detection method) according to this embodiment. The microcomputer 20 (the processor 23 and the absolute position calculator 24) executes the processing according to the computer program. In the following description, S represents a step.

The microcomputer 20 that has started the absolute position calculation process acquires the position information from the sensor 2 in S051, and performs signal processing and synchronization calculation on the acquired signal in S052. Thereby, a phase difference signal θ is obtained_XAnd wave number N thereof_X。

Next, the microcomputer 20 acquires the division signals from the photo interrupters PI _1 and PI _2 in S053, and determines which determination region the division signals indicate in S054. As shown in fig. 9, the microcomputer 20 determines the determination area as a when the division signal becomes L and proceeds to S056, and proceeds to S055 otherwise. In S055, if the division signal is H and L, the determination region is determined as B, and the flow proceeds to S057. Otherwise (if the division signals are H and H), the determination region is determined to be C and the flow proceeds to S058.

In S056, the microcomputer 20 uses the phase difference signal θ_XWave number N of_XSpecifying (determining) the phase difference signal θ_WWave number N of_W. Then, the microcomputer 20 applies the wave number N_XCompares with a predetermined value (predetermined code), and specifies the wave number N based on the result_W. More specifically, if N is_XIs 7 or more as a predetermined value, or if the first wave 41a shown in fig. 9 is indicated, the microcomputer 20 proceeds to S059 and N is set_WIs set to 0. If N is present_XIs 6 or less as a predetermined value, or if the second wave 41b is indicated, the flow advances to S060 and N is set_WIs set to 1.

In S057, the microcomputer 20 uses the phase difference signal θ_XWave number N of_XSpecifying a phase difference signal theta_WWave number N of_W. If N is present_XIs 5 or more as a predetermined value, or if the second wave 41b is indicated, the microcomputer 20 proceeds to S061 and shifts N_WIs set to 1. If N is present_XIs 4 or less, or if the third wave 41c is indicated, the flow proceeds to S062 and N is set_WSet to 2.

In S058, the microcomputer 20 uses the phase difference signal θ_XWave number N of_XSpecifying a phase difference signal theta_WWave number N of_W. If N is present_XIs 3 or more as a predetermined value, or if the third wave 41c is instructed, the microcomputer 20 proceeds to S063 and N_WSet to 2. If N is present_XIs 2 or less, or if the fourth wave 41d is indicated, the flow advances to S064 to shift N_WSet to 3.

Thus determining the current phase difference signal theta_XWave number N of_XAnd phase difference signal (theta)_W) Wave number N of 41_WThe microcomputer 20 of (1) calculates the current absolute position θ according to the following expression (7) in S065, and ends the processing.

θ＝(360°×10×N_W+360°×N_X+θ_X-θ_X0)×30 (7)

However, theta_X0The reference position, which is the left end of the absolute position detection range 40 shown in fig. 9, is determined from the phase difference signal θ_XThe position of the representation. Due to theta_X0Contains an error component due to an attachment error of the reflective scale 1 and the sensor 2, etc., and therefore θ will be generated in the manufacturing process of the lens barrel_X0Written into a memory area of the microcomputer 20. With regard to the last term × 30 in equation (7), the absolute position when the device is powered on is represented by θ_XFinally determined and increased and decreased from pitch P in FIG. 5D₁Obtained theta_ZThe range of the absolute position theta is adjusted using the subsequent change in position.

In this embodiment, when the pitch P is to be reduced₁A phase difference signal theta as an intermediate signal when set to 0.1mm_XThe detection unit of (2) corresponds to a detection length of 3 mm. The photo interrupter PI _1(30_1) is arranged such that the signal is at the phase difference signal theta_XWave number N in_XWave and wave number N of 5_XThe boundary between the waves of 6 is changed by the light shielding plate 31. However, the phase difference signal θ as the uppermost signal is not erroneously determined_WWave number N of_WSince the switching of the signal from the photo interrupter PI _1 can be located within one of the waves of wave numbers 5 and 6, it can be within ± 3mm from the boundary between the waves. In other words, high relative positional accuracy of the photo interrupter PI _1 and the light shielding plate 31 is not required. The same applies to the relative positional accuracy between the photo interrupter PI _2 and the light shielding plate 31.

Second embodiment

Referring now to fig. 11, a description will be given of the calculation of the absolute position according to the second embodiment of the present invention. The position detection device according to this embodiment has the same configuration as that of the first embodiment (fig. 6), and detects the rotational position of the rotating ring 32 of the lens barrel described with reference to fig. 7A and 7B.

Fig. 11 shows a phase signal 141 (1) as a first signal in the absolute position detection range 14041a to 141 d). The phase signal 141 is obtained by obtaining the phase signal having the pitch Q in FIG. 5B and FIG. 5C₁Phase signal theta of_YConverted into wave number N_YThe absolute value of the signal. The range in which the phase of the phase signal 141 in the position detection direction changes from 0 to 27000 ° is one detection unit (first relative movement amount) of the phase signal 141. In fig. 11, the length of the absolute position detection range 140 is 2.3 times the detection unit of the phase signal 141, and three boundaries between the detection units (the first wave 141a to the fourth wave 141d) exist in the absolute position detection range 140. Assume that the wave number of the phase signal 141 is N_F. Thus, the wave number of the first wave 141a of the phase signal 141 is N_FThe wave number of the second wave 141b is N when equal to 0_FThe wave number of the third wave 141c is N_FThe wave number of the fourth wave 141d is N_F＝3。

A phase signal θ corresponding to the second signal shown in fig. 5D superimposed on the phase signal 141_ZWave number N of_ZAnd the indicated wave number N displayed on both sides_ZThe vertical lines (0 to 299) show the boundaries serving as determination references from the first wave 141a to the fourth wave 141d of the phase signal 141.

This embodiment uses the phase signal θ_ZThe absolute position is calculated. This embodiment divides the absolute position detection range 140 into three determination regions A, B and C, similarly to the first embodiment. The length in the position detection direction of each determination region is shorter than one detection unit of the phase difference signal 141. The determination regions A, B and C each include only one boundary between two adjacent detection units (waves) in the phase difference signal 141 inside both ends thereof.

Referring now to the flowchart in fig. 12, a description will be given of the absolute position calculation processing according to this embodiment. The microcomputer 20 (the processor 23 and the absolute position calculator 24) executes the processing according to the computer program.

The microcomputer 20 having started the absolute position calculation process acquires the position information from the sensor 2 in S151, and performs signal processing and synchronization calculation on the acquired signal in S152. Thereby, a phase signal θ is obtained_ZAnd wave number N thereof_Z。

Next, the microcomputer 20 acquires the division signals from the photo interrupters PI _1 and PI _2 in S153, and determines which determination region the division signals indicate in S154. If the division signal is L and L, the microcomputer 20 determines the determination area as a, and the flow proceeds to S156, otherwise to S155. In S155, if the division signal is H and L, the determination region is determined as B and the flow proceeds to S157. Otherwise (if the division signals are H and H), the determination region is determined to be C and the flow proceeds to S158.

In S156, the microcomputer 20 uses the phase signal θ_ZWave number N of_ZSpecifying (determining) the wave number N of the phase signal 141_F. If N is present_ZIs 210 or more as a predetermined value (predetermined code), or if the first wave 141a shown in fig. 11 is indicated, the microcomputer 20 proceeds to S159 and N is set_FIs set to 0. If N is present_ZEqual to or less than 209 as a predetermined value, or if the second wave 141b is indicated, the flow proceeds to S160 and N is set_FIs set to 1.

In S157, the microcomputer 20 uses the phase signal θ_ZWave number N of_ZSpecifying the wavenumber N of the phase signal 141_F. If N is present_ZIs 150 or more as a predetermined value, or if the second wave 141b is instructed, the microcomputer 20 proceeds to S161 and N is set_FIs set to 1. If N is present_ZIs 149 or less as a predetermined value (if the third wave 141c is indicated), the flow advances to S162 to change N_FSet to 2.

In S158, the microcomputer 20 uses the phase signal θ_ZWave number N of_ZSpecifying the wavenumber N of the phase signal 141_F. If N is present_ZIs 90 or more as a predetermined value, or if the third wave 141c is instructed, the microcomputer 20 proceeds to S163 and N_FSet to 2. If N is present_ZIs 89 or less as a predetermined value, or if the fourth wave 141d is indicated, the flow advances to S164 to N_FSet to 3.

In this way, the current phase difference signal θ is determined_ZWave number N of_ZWave number N of sum phase difference signal 141_FThe microcomputer 20 of (1) calculates the current absolute position θ according to the following expression (8) in S165, and ends the processing.

θ＝27000°×4×N_F+360°×N_Z+θ_Z-θ_Z0(8)

θ_Z0The reference position, which is the left end of the absolute position detection range 140 shown in fig. 11, is determined from the phase difference signal θ_ZThe position of the representation. Due to theta_Z0Contains an error component due to an attachment error of the reflective scale 1 and the sensor 2, etc., and therefore θ will be generated in the manufacturing process of the lens barrel_Z0Written into a memory area of the microcomputer 20.

The absolute position calculation accuracy is the phase difference signal θ in fig. 5C similar to that of the first embodiment_XIs also similar to the phase signal θ in fig. 5D of the second embodiment_ZCan be based on the calculation load, the accuracy required for the absolute position of the lens barrel, whether or not the synchronization calculation accuracy can be ensured to reach the phase signal theta_ZEtc. are determined.

Third embodiment

A position detection apparatus according to a third embodiment of the present invention is described next. The first and second embodiments divide the determination area using the light-shielding plate 31 provided on the rotating ring 32 holding the reflective scale 1 and the photo interrupters 30_1 and 30_2 fixed to the fixed cylinder. On the other hand, the embodiment divides the determination region by another method. The absolute position calculation process is the same as that in each of the first embodiment or the second embodiment.

Fig. 13A and 13B show a specific configuration when the position detection apparatus according to the present embodiment is used for a lens barrel. The figure shows a known lens moving mechanism mounted on an exchangeable lens barrel or the like. Reference numeral 210 denotes a linear movement guide cylinder having three linear grooves 210a, and 211 denotes a cam cylinder having three cam grooves 211 a. The lens barrel 212, three cam follower pins 213 are fixed to the lens barrel 212 at equal angles in the circumferential direction. The three cam follower pins 213 are held between the three linear grooves 210a and the three cam grooves 211a to support the lenses, and the lens barrel moves forward and backward as the cam barrel 211 rotates.

The rotational driving force is transmitted to the cam cylinder 211 via the drive key 214. The area detection lift portion 231 has an end surface 231b provided at a rear end portion of the cam barrel 211, and the area detection lift portion 231 includes a first end surface 231a and a second end surface 231b, and the second end surface 231b is formed one stage ahead of the first end surface 231a and is formed in a different circumferential direction range from the first end surface 231 a.

The micro switches 230_1, 230_2, and 230_3 are held by a fixed cylinder, not shown, at a position opposite to the area detection lift portion 231. Each micro switch outputs an L signal (division signal) with its switch pin facing the second end face 231b, and outputs an H division signal when the switch pin is pressed by the first end face 231 a. The micro switches 230_1, 230_2, and 230_3 as at least one detection portion and the area detection lifting unit 231 as a detected portion are arranged side by side in the rotation direction of the cam cylinder 211 as a position detection direction.

Referring now to fig. 14, a description will be given of calculation of an absolute position according to this embodiment. The upper side of fig. 14 shows the phase difference signal (θ) as shown in fig. 5A in the absolute position detection range 240_W)241(241a to 241 c). The range in which the phase of the phase difference signal 241 in the position detection direction changes from 0 to 360 ° is one detection unit of the phase difference signal 241. In fig. 14, the length of the absolute position detection range 240 is 2.3 times as long as the detection unit of the phase difference signal 241, and two boundaries between the detection units (the first wave 241a to the third wave 241c) exist in the absolute position detection range 240. Suppose N_WIs the wave number of the phase difference signal 241. Then, the wave number of the first wave 241a of the phase difference signal 241 is N_WThe wave number of the second wave 241b is N when equal to 0_W1, and the wave number of the third wave 241c is N_W＝2。

The vertical line shows the phase difference signal θ shown in fig. 5B superimposed on the phase difference signal 241_XOf two adjacent waves. Attached between boundaries or for phase difference signal theta_XThe number 0 to 9 of each detection unit of (1) is a phaseDifference signal theta_XWave number N of_X。

The lower side of fig. 14 shows the position (shown in black) of the area detection lifting part 231 moving in the position detection direction, as well as the reflective scale 1 and the division signal (H or L) from the micro switches (SW _1, SW _2, SW _3)230_1, 230_2, and 230_ 3.

This embodiment uses the phase difference signal θ_XThe absolute position is calculated. For each wave, a phase difference signal θ_XChanging its phase from 0 to 360 deg.. The absolute position detection range 240 is divided into five determination regions A, B, C, D and E by the region detection lifting portion 231 and the micro switches 230_1, 230_2, and 230_ 3. Each determination region in the position detection direction is shorter than one detection unit of the phase difference signal 241. The determination regions B and D each include only one boundary between two adjacent detection units (waves) in the phase difference signal 241 inside both ends thereof.

The rotational positions 1 and 6 of the cam barrel 211 indicate both end positions of the absolute position detection range 240. From the rotational position 1 to the rotational position 2 (in the determination region a), the division signals output from the micro switches 230_1, 230_2, and 230_3 are H, H and L, respectively. From the rotational position 2 to the rotational position 3 (in the determination region B), the division signal from the micro switch 230_3 changes from L to H, and the division signals from the micro switches 230_1, 230_2, and 230_3 change to H, H and H, respectively. From the rotational position 3 to the rotational position 4 (in the determination region C), the division signal from the micro switch 230_1 changes from H to L, and the division signals from the micro switches 230_1, 230_2, and 230_3 change to L, H and H, respectively. From the rotational position 4 to the rotational position 5 (in the determination region D), the division signal from the micro switch 230_2 changes from H to L, and the division signals from the micro switches 230_1, 230_2, and 230_3 change to L, L and H, respectively. From the rotational position 5 to the rotational position 6 (in the determination region E), the division signal from the micro switch 230_3 changes from H to L, and the division signals from the micro switches 230_1, 230_2, and 230_3 change to L, L and L, respectively.

Referring now to the flowchart in fig. 15, a description will be given of the absolute position calculation processing according to this embodiment. The microcomputer 20 (the processor 23 and the absolute position calculator 24) executes the processing according to the computer program.

The microcomputer 20 having started the absolute position calculation process acquires the position information from the sensor in S251, and performs signal processing and synchronization calculation on the acquired signal in S252. Thereby, a phase difference signal θ is obtained_XAnd wave number N thereof_X。

Next, the microcomputer 20 acquires the division signals from the micro switches 230_1, 230_2, and 230_3 in S253, and determines which determination region the division signals indicate in S254. If the division signal is H, H and L, the microcomputer 20 determines that the determination region is a and proceeds to S260, otherwise proceeds to S255. The microcomputer 20 compares N with S260_WIs set to 0.

In S255, if the division signals are H, H and H, the microcomputer 20 proceeds to S258, otherwise proceeds to S256. In S256, if the division signals are L, H and H, the microcomputer 20 determines the determination region as C and proceeds to S263 to determine N_WSet to 1, otherwise proceed to S257. In S257, if the division signals are L, L and H, the microcomputer 20 proceeds to S259. Otherwise, the microcomputer 20 determines the determination region as E and proceeds to S266 to determine N_WSet to 2.

In S258, the microcomputer 20 uses the phase difference signal θ_XWave number N of_XSpecifying (determining) the phase difference signal θ_WWave number N of_W. If N is present_XIs 5 or more as a predetermined value (predetermined code), or if the first wave 241a shown in fig. 11 is indicated, the microcomputer 20 proceeds to S261 and N is set_WIs set to 0. If N is present_XIs 4 or less as a predetermined value, or if the second wave 241b is indicated, the flow proceeds to S262 and N is set_WIs set to 1.

In S259, the microcomputer 20 uses the phase difference signal θ_XWave number N of_XSpecifying a phase difference signal theta_WWave number N of_W. If N is present_XIs 5 or more as a predetermined value, or if the second wave 241b is instructed, the microcomputer 20 proceeds to S264 and N is set_WIs set to 1. If N is present_XIs 4 or less, or if a third wave 241c is indicated,the flow advances to S265 to shift N_WSet to 2.

The current phase difference signal 0 has been determined in this way_XWave number N of_XAnd phase difference signal (theta)_W)241 wave number N_WThe microcomputer 20 of (1), in S267, calculates the current absolute position θ by equation (7) described in the first embodiment, and ends the flow. θ in the formula (7) is similar to that of the first embodiment_X0The reference position, which is the left end of the absolute position detection range 240 shown in fig. 14, is determined from the phase difference signal θ_XThe position of the representation.

This embodiment increases the number of divisions of the detection range of the same length from 3 to 5 compared to the first embodiment, and with respect to the wave number N which is a predetermined value for determining the second region and the fourth region including the boundary of the upper signal_XSetting boundaries on both sides of the determination region to wave numbers N _X7 and 2. Since there is a wider space at the boundary position than in the first embodiment, the setting accuracy can be relaxed. As shown in fig. 7A and 7B, the first embodiment determines the area by the light shielding plate 31 and the photo interrupters 30_1 and 30_2 integrated with the rotating ring 32 to which the reflective scale 1 is fixed. When the light shielding plate 31 and the photo interrupters 30_1 and 30_2 are not provided on the rotating ring 32 for space reasons and the region is determined by another portion as in the present embodiment, the accuracy becomes lower than that of the example in the first embodiment due to the mechanical accuracy, backlash, and the like of the intervening members. However, since this embodiment relaxes the region determination accuracy, even if the region is divided at a portion other than the member to which the reflective scale is attached, erroneous detection can be sufficiently prevented.

Fourth embodiment

A fourth embodiment of the present invention will now be described. Fig. 16A and 16B show a specific configuration of the position detecting device according to this embodiment for an interchangeable lens or lens barrel of a camera. The lens barrel includes: a lens holding frame 312 configured to hold the lens 300; a guide rod 310 configured to guide the lens holding frame 312 in the optical axis direction; and a rotation preventing bar 311 configured to prevent the lens holding frame 312 from rotating around the guide bar 310.

The reflective scale 301 is fixed to the lens holding frame 312 to extend in the optical axis direction. The sensor 302 is fixed in a not-shown fixed cylinder at a position facing the reflective scale 301. The reflective scale 301 and the sensor 302 are configured similarly to the first embodiment.

A Photo Interrupter (PI)330 is fixed to the fixed barrel, and a light blocking plate 331 is integrated with the lens holding frame 312. In fig. 16A, the light shielding plate 331 is not inserted into a space between the light emitting portion and the light receiving portion of the photo interrupter 330, and is in a light transmitting state. In fig. 16B, when the lens holding frame 312 is moved in the arrow direction along the optical axis direction, the light shielding plate 331 enters a space between the light emitting portion and the light receiving portion of the photo interrupter 330 and is in a light shielding state.

Referring now to fig. 17, a description will be given of calculation of an absolute position according to this embodiment. The upper side in fig. 17 shows the phase difference signal (θ) shown in fig. 5A in the absolute position detection range 340_W)341(341a to 341 c). The range in which the phase of the phase difference signal 341 in the position detection direction changes from 0 to 360 ° is one detection unit of the phase difference signal 341. In fig. 17, the length of the absolute position detection range 340 is 1.5 times as long as the detection unit of the phase difference signal 341, and two boundaries between the detection units (the first wave 341a to the third wave 341c) exist within the absolute position detection range 340. The absolute position detection range 340 includes three detection units of the phase difference signal 341. Suppose N_WIs the wave number of the phase difference signal 341. Thus, the wave number of the first wave 341a of the phase difference signal 341 is N_WThe wave number of the second wave 341b is N as 0_W1, and the wave number of the third wave 341c is N_W＝2。

The vertical line shows the phase difference signal θ shown in fig. 5B as an intermediate signal superimposed on the phase difference signal 341_XOf two adjacent waves. Attached between boundaries or for phase difference signal theta_XIs a phase difference signal theta_XWave number N of_X。

The lower side of fig. 17 shows the position (shown in black) where the light shielding plate 331 moves in the position detecting direction, as well as the reflective scale 1 and the division signal (H or L) from the photo interrupter 330.

This embodiment uses the phase difference signal θ_XThe absolute position is calculated. For each wave, a phase difference signal θ_XChanging its phase from 0 to 360 deg.. The absolute position detection range 340 is divided into two determination regions a and B by the light shielding plate 331 and the photo interrupter 330. Each determination region in the position detection direction is shorter than one detection unit of the phase difference signal 341. The determination regions a and B each include only one boundary between two adjacent detection units (waves) in the phase difference signal 341 inside both ends thereof.

Referring now to the flowchart in fig. 18, a description will be given of the absolute position calculation processing according to this embodiment. The microcomputer 20 (the processor 23 and the absolute position calculator 24) executes the processing according to the computer program.

The microcomputer 20 that has started the absolute position calculation process acquires the position information from the sensor 302 in S451, and performs signal processing and synchronization calculation on the acquired signal in S452. Thereby, a phase difference signal θ is obtained_XAnd wave number N thereof_X。

Next, the microcomputer 20 obtains a division signal from the photo interrupter 330 in S453, and determines which determination region the division signal indicates in the following S454. As shown in fig. 17, when the division signal is L, the microcomputer 20 determines the determination area as a and proceeds to S455, and otherwise determines the determination area as B and proceeds to S456.

In S455, the microcomputer 20 uses the phase difference signal θ_XWave number N of_XSpecifying (determining) the phase difference signal θ_WWave number N of_W. If N is present_XIs 7 or more as a predetermined value (predetermined code), or if the first wave 341a shown in fig. 17 is indicated, the microcomputer 20 proceeds to S457 and N is set_WIs set to 0. If N is present_XIs 6 or less as a predetermined value, or if the second wave 341b is indicated, the flow proceeds to S458 and N is set_WIs set to 1.

In S456, the microcomputer 20 uses the phase difference signal θ_XWave number N of_XSpecifying a phase difference signal theta_WWave number N of_W. If N is present_XIs 5 or more as a predetermined value, or if the second wave 341b is indicated, the microcomputer 20 proceeds to S459 and shifts N_WIs set to 1. If N is present_XIs 4 or less, or if the third wave 341c is indicated, the flow advances to S460 to shift N_WSet to 2.

The current phase difference signal θ has been determined in this way_XWave number N of_XAnd phase difference signal (theta)_W)341 wave number N_WThe microcomputer 20 of (1), in S461, calculates the current absolute position θ by the expression (7) described in the first embodiment, and ends the processing. θ in the formula (7) is similar to that of the first embodiment_X0The reference position, which is the left end of the absolute position detection range 340 shown in fig. 17, is determined from the phase difference signal θ_XThe position of the representation.

The first to fourth embodiments described above can detect the absolute position of the movable member with high accuracy without restricting the amount of movement of the movable member (32, 211, 312).

The first to fourth embodiments fix the scale to the movable member and fix the sensor to the fixed member, but the scale may be fixed to the fixed member and the sensor may be fixed to the movable member. The first to fourth embodiments describe using a reflective scale as the scale, but a transmissive scale may be used. The divider is not limited to the dividers illustrated in the first to fourth embodiments, and any configuration may be used as long as it can generate the division signal for dividing the absolute position detection range into the plurality of determination areas.

Although the first to fourth embodiments describe the number (wave number) as a code added to each detection unit (wave) of the second signal, the code may not be a number and may be different for each detection unit.

Although the first to fourth embodiments have described the lens barrel for an optical apparatus (such as an interchangeable lens and a camera), other embodiments of the present invention are applicable to various apparatuses other than the optical apparatus.

Each embodiment can detect the absolute position of the movable member with high accuracy without restricting the amount of movement of the movable member.

OTHER EMBODIMENTS

The embodiment(s) of the present invention may also be implemented by: a computer of a system or apparatus that reads and executes computer-executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a "non-transitory computer-readable storage medium") to perform the functions of one or more of the above-described embodiment(s), and/or that includes one or more circuits (e.g., an Application Specific Integrated Circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s); and computer-implemented methods by the system or apparatus, e.g., reading and executing computer-executable instructions from a storage medium to perform the functions of one or more of the above-described embodiment(s) and/or control the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may include one or more processors (e.g., Central Processing Unit (CPU), Micro Processing Unit (MPU)) and may include a separate computer or a network of separate processors to read out and execute computer-executable instructions. The computer-executable instructions may be provided to the computer, for example, from a network or a storage medium. For example, the storage medium may include one or more of the following: hard disk, Random Access Memory (RAM), read-only memory (ROM), memory for a distributed computing system, optical disk (e.g., Compact Disk (CD), Digital Versatile Disk (DVD), or blu-ray disk (BD)^TM) Flash memory devices, memory cards, and the like.

The embodiments of the present invention can also be realized by a method in which software (programs) that perform the functions of the above-described embodiments are supplied to a system or an apparatus through a network or various storage media, and a computer or a Central Processing Unit (CPU), a Micro Processing Unit (MPU) of the system or the apparatus reads out and executes the methods of the programs.

While the present invention has been described with respect to the exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.