阅读说明：本技术 一种光透过率调节装置及照明系统 (Light transmittance adjusting device and lighting system ) 是由 章富平 王彩红 湛宾洲 郁健 周伟 于 2018-09-13 设计创作，主要内容包括：本发明公开了一种光透过率调节装置及照明系统。所述光透过率调节装置包括调节本体以及与所述调节本体连接的驱动部；所述驱动部用于带动所述调节本体沿第一方向或所述第一方向的反方向运动；所述调节本体包括基板以及至少一个光调节单元,所述光调节单元包括形成于所述基板上且等间距分布的多个凹槽,所述凹槽沿所述第一方向延伸；被调节光斑落于所述光调节单元所在区域内；沿所述第一方向,所述凹槽的宽度逐渐增大或减小。本发明实施例提供的技术方案,使得光透过率调节装置的结构简单,成本低,实现了连续光透过率调节,能够以较小空间尺寸的调节本体实现较高的光透过率调节分辨率。(The invention discloses a light transmittance adjusting device and an illuminating system. The light transmittance adjusting device comprises an adjusting body and a driving part connected with the adjusting body; the driving part is used for driving the adjusting body to move along a first direction or the direction opposite to the first direction; the adjusting body comprises a substrate and at least one light adjusting unit, the light adjusting unit comprises a plurality of grooves which are formed on the substrate and distributed at equal intervals, and the grooves extend along the first direction; the adjusted light spot falls in the area where the light adjusting unit is located; the width of the groove gradually increases or decreases along the first direction. According to the technical scheme provided by the embodiment of the invention, the light transmittance adjusting device is simple in structure and low in cost, continuous light transmittance adjustment is realized, and higher light transmittance adjustment resolution can be realized by using the adjusting body with smaller space size.)

1. A light transmittance adjusting device is characterized by comprising an adjusting body and a driving part connected with the adjusting body;

the driving part is used for driving the adjusting body to move along a first direction or the direction opposite to the first direction;

the adjusting body comprises a substrate and at least one light adjusting unit, the light adjusting unit comprises a plurality of grooves which are formed on the substrate and distributed at equal intervals, and the grooves extend along the first direction; the adjusted light spot falls in the area where the light adjusting unit is located;

the width of the groove gradually increases or decreases along the first direction.

2. The light transmittance adjusting device according to claim 1, wherein the at least one light adjusting unit includes a first light adjusting unit, a second light adjusting unit, and a third light adjusting unit, wherein a minimum width of the groove in the third light adjusting unit is larger than a maximum width of the groove in the second light adjusting unit, and wherein a minimum width of the groove in the second light adjusting unit is larger than a maximum width of the groove in the first light adjusting unit.

3. The light transmittance adjustment device according to claim 2, wherein the light transmittance range of the third light adjustment means is 65% to 75%, the light transmittance adjustment range of the second light adjustment means is 45% to 55%, and the light transmittance adjustment range of the first light adjustment means is 20% to 30%.

4. The light transmittance adjusting apparatus according to claim 1, wherein the adjusting body further comprises a full light transmission unit, the full light transmission unit is circular in shape, and the diameter of the circular shape is larger than the diameter of the adjusted light spot.

5. The light transmittance adjustment device according to claim 1, characterized in that the at least one light adjustment unit includes a fourth light adjustment unit; along in the first direction, in the fourth light adjusting unit, the width of the groove gradually increases from zero to communicate with the adjacent groove.

6. The light transmittance adjustment device according to claim 1, wherein a straight line perpendicular to the first direction is a reference line, and the plurality of grooves have equal widths on any one of the reference lines of the light adjustment unit.

7. The light transmittance adjusting device according to claim 1, wherein a straight line perpendicular to the first direction is a reference line, and passes through any one of the reference lines of the light adjusting means, a midpoint of the light adjusting means is a first center, a width of the groove at a distance equal to the first center is equal, and the width of the groove decreases and then increases in an extending direction of the reference line with the center as an inflection point.

8. The light transmittance adjustment device according to claim 1, wherein the substrate has a circular shape, and the first direction is a direction in which sides of the circular shape extend.

9. The light transmittance adjustment device according to claim 1, wherein the substrate has a rectangular shape, and the first direction is an extending direction of a long side of the rectangular shape.

10. An illumination system comprising the light transmittance adjusting apparatus according to any one of claims 1 to 9.

Technical Field

The embodiment of the invention relates to a light transmittance adjusting technology, in particular to a light transmittance adjusting device and an illumination system.

Background

The illumination system is an important component of the lithography machine, and in order to avoid the influence of different light powers of at least two mercury lamps in the illumination system on the precision of the lithography machine, a light transmittance adjusting device is needed to adjust the light emitted by each mercury lamp.

Fig. 1 is a schematic structural view of an adjusting body in a light transmittance adjusting apparatus in the prior art. As shown in fig. 1, the adjustment body includes a sector-shaped base plate 201 and a plurality of circular holes 202 with different diameters formed on the sector-shaped base plate 201, and the sector-shaped base plate 201 can rotate around the center of the sector-shaped circle. For the adjusting body shown in fig. 1, in the process of rotating the fan-shaped substrate 201, the diameter of the circular hole in the coverage area of the adjusted light spot changes, and further the light transmittance adjustment is realized. The light transmittance range of the adjustment body shown in fig. 1 is limited, the upper limit is only about 50%, and further, since the plurality of circular holes 202 are separated from each other, continuous transmittance adjustment cannot be achieved, and a high light transmittance adjustment resolution cannot be achieved with a small space size. In order to solve the above problems, the prior art provides an optical compensator, which can change the light transmittance by using the way that the light transmittances of the lenses are different at different angles, but because two lenses are needed, the optical compensator occupies a large space in the direction of the optical axis, has a complex structure, and has a high cost due to the difficulty of the mirror surface coating process.

Disclosure of Invention

The invention provides a light transmittance adjusting device and a lighting system, which are used for simplifying the structure of the light transmittance adjusting device, reducing the cost of the light transmittance adjusting device, realizing continuous light transmittance adjustment and realizing higher light transmittance adjustment resolution by using an adjusting body with smaller space size.

In a first aspect, an embodiment of the present invention provides a light transmittance adjusting device, including an adjusting body and a driving portion connected to the adjusting body;

the driving part is used for driving the adjusting body to move along a first direction or the direction opposite to the first direction;

the adjusting body comprises a substrate and at least one light adjusting unit, the light adjusting unit comprises a plurality of grooves which are formed on the substrate and distributed at equal intervals, and the grooves extend along the first direction; the adjusted light spot falls in the area where the light adjusting unit is located;

the width of the groove gradually increases or decreases along the first direction.

In a second aspect, an embodiment of the present invention further provides an illumination system, including the light transmittance adjusting device according to the first aspect.

The light transmittance adjusting device provided by the embodiment of the invention comprises an adjusting body and a driving part connected with the adjusting body, wherein the driving part is used for driving the adjusting body to move along a first direction or the opposite direction of the first direction, the adjusting body comprises a substrate and at least one light adjusting unit, the light adjusting unit comprises a plurality of grooves which are formed on the substrate and are distributed at equal intervals, the grooves extend along the first direction, adjusted light spots are located in the area of the light adjusting unit, and the width of the grooves gradually increases or decreases along the first direction, the light transmissivity adjusting device has simple structure and low cost, in addition, the groove penetrates through the light adjusting unit along the first direction, the width of the groove is gradually increased or decreased, the continuous light transmissivity adjustment is realized, after the gradual change of the groove width is further adjusted, the adjustment body with smaller space size can realize higher light transmittance adjustment resolution.

Drawings

In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, a brief description is given below of the drawings used in describing the embodiments. It should be clear that the described figures are only views of some of the embodiments of the invention to be described, not all, and that for a person skilled in the art, other figures can be derived from these figures without inventive effort.

FIG. 1 is a schematic structural diagram of an adjusting body in a light transmittance adjusting apparatus in the prior art;

fig. 2 is a schematic structural diagram of a light transmittance adjusting device according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of an adjustment body according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a light adjusting unit according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of another light adjusting unit according to an embodiment of the present invention;

FIG. 6 is a simulation result of static uniformity after light passes through an adjustment body;

FIG. 7 is a simulation result of integration uniformity after light passes through the adjustment ontology;

FIG. 8 is a simulation result of pupil uniformity after light passes through the adjustment body;

FIG. 9 is a schematic structural diagram of another adjustment body provided in accordance with an embodiment of the present invention;

FIG. 10 is a schematic structural diagram of another adjustment body provided in accordance with an embodiment of the present invention;

fig. 11 is a schematic structural diagram of an illumination system according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some but not all of the relevant aspects of the present invention are shown in the drawings. Before discussing exemplary embodiments in more detail, it should be noted that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although a flowchart may describe the operations (or steps) as a sequential process, many of the operations can be performed in parallel, concurrently or simultaneously. In addition, the order of the operations may be re-arranged. The process may be terminated when its operations are completed, but may have additional steps not included in the figure. The processes may correspond to methods, functions, procedures, subroutines, and the like.

Fig. 2 is a schematic structural diagram of a light transmittance adjusting device according to an embodiment of the present invention. As shown in fig. 2, the light transmittance adjusting apparatus includes an adjusting body 100 and a driving part 200 connected to the adjusting body 100, wherein the driving part 200 is used for driving the adjusting body 100 to move along a first direction (not shown in fig. 2) or a direction opposite to the first direction. Fig. 3 is a schematic structural diagram of an adjustment body according to an embodiment of the present invention. As shown in fig. 3, adjust the body and include base plate 110 and at least one light and adjust the unit, light adjusts the unit including forming in a plurality of recesses 101 that just equidistant distribution on the base plate 110, recess 101 is followed first direction X extends, is adjusted facula 102 and is fallen on light adjusts the unit place region in, follows first direction X, the width crescent of recess 101.

The equal pitch distribution means that the plurality of grooves 101 in the light adjusting unit are equally spaced on any straight line perpendicular to the first direction X and penetrating the light adjusting unit. In addition, in other embodiments of the present embodiment, the width of the groove 101 may be gradually reduced along the first direction X.

Optionally, the substrate 110 may be a metal sheet, and the thickness may range from greater than 0 mm to 2 mm. It is noted that the power of the light forming the modulated spot 102 is typically high, and therefore the material of the substrate 110 is a metal material to avoid damage to the substrate 110 during normal use.

For example, in the design process of the adjustment body, a plurality of initial grooves with unchanged widths may be preset, and a side of each initial groove close to the center of the circle of the substrate 110 is taken as a first side, and a side of each initial groove far from the center of the circle of the substrate 110 is taken as a second side, so that a circle in which the first sides of the plurality of initial grooves are located in the same light adjustment unit is a concentric circle with a first point as the center of the circle, a circle in which the second sides are located is a concentric circle with a second point as the center of the circle, and the first point and the second point coincide, optionally, the center of the circle of the substrate 110. And then adjusting the positions of the first point and the second point to enable the first point and the second point to move a first distance and a second distance respectively along the vertical direction of the first diameter, wherein the first distance is smaller than the second distance, and the first diameter is the diameter of a circle where any first edge is located before the first point and the second point are not moved. And correspondingly adjusting the positions of the first edge and the second edge of each initial groove to form a plurality of grooves 101, so that the edge of each groove 101 close to the center of the circle of the substrate 110 is a concentric circle with the adjusted first point as the center of the circle, and the edge far away from the center of the circle of the substrate 110 is a concentric circle with the adjusted second point as the center of the circle. It should be noted that, in the above example, the forming manner of the groove 101 is described by taking the adjustment of the center of the circle as an example, in other embodiments of this embodiment, the groove 101 may also be formed in other manners, for example, by adjusting the curvature radius, which is not specifically limited in this embodiment.

It should be noted that, in order to enable the adjusting body to adjust the light transmittance of the whole adjusted light spot 102, the adjusted light spot 102 is set to fall within the area of the light adjusting unit in the present embodiment, and preferably, as shown in fig. 3, the diameter of the adjusted light spot 102 is equal to the width of the light adjusting unit.

The light transmittance adjusting device provided by this embodiment includes an adjusting body 100 and a driving portion 200 connected to the adjusting body 100, the driving portion 200 is used for driving the adjusting body 100 to move along a first direction X or an opposite direction of the first direction X, the adjusting body 100 includes a substrate 110 and at least one light adjusting unit, the light adjusting unit includes a plurality of grooves 101 formed on the substrate 110 and distributed at equal intervals, the grooves 101 extend along the first direction X, the adjusted light spots 102 fall in an area where the light adjusting unit is located, and the width of the grooves 101 gradually increases along the first direction X, so that the light transmissivity adjusting apparatus has a simple structure and a low cost, and in addition, the groove 101 penetrates the light adjusting unit in the first direction X and has a width gradually increased or decreased, thereby realizing continuous light transmissivity adjustment, after the gradual change of the width of the groove 101 is further adjusted, the adjustment body with smaller space size can realize higher light transmittance adjustment resolution.

For example, as shown in fig. 3, the at least one light adjusting unit includes a first light adjusting unit 121, a second light adjusting unit 122, and a third light adjusting unit 123, wherein a minimum width of the groove 101 in the third light adjusting unit 123 is greater than a maximum width of the groove 101 in the second light adjusting unit 122, and a minimum width of the groove 101 in the second light adjusting unit 122 is greater than a maximum width of the groove 101 in the first light adjusting unit 121.

It should be noted that, since the width of the groove 101 in the first direction X is gradually increased or decreased, when the minimum width of the groove 101 in the third light adjusting unit 123 is set to be greater than the maximum width of the groove 101 in the second light adjusting unit 122, and the minimum width of the groove 101 in the second light adjusting unit 122 is set to be greater than the maximum width of the groove 101 in the first light adjusting unit 121, the minimum light transmittance of the third light adjusting unit 123 is greater than the maximum light transmittance of the second light adjusting unit 122, and the minimum light transmittance of the second light adjusting unit 122 is greater than the maximum light transmittance of the first light adjusting unit 121, there is no overlapping portion between the light transmittance range of the first light adjusting unit 121, the light transmittance range of the second light adjusting unit 122, and the light transmittance range of the third light adjusting unit 123, so as to avoid the waste of space caused by the repeated setting, the corresponding light transmittance range can be changed by adjusting the width of the plurality of grooves 101 in each light adjusting unit and the pitch of the grooves 101.

Optionally, the light transmittance range of the third light adjusting unit 123 may be 65% to 75%, the light transmittance range of the second light adjusting unit 122 may be 45% to 55%, and the light transmittance range of the first light adjusting unit 121 may be 20% to 30%.

It should be noted that 65% -75%, 45% -55% and 20% -30% are three light transmittance ranges commonly used in the prior art, and this embodiment sets the light transmittance ranges of three light adjusting units on the same adjusting body to the above three ranges respectively, so that the practicability of the light transmittance adjusting device is increased, and the light adjusting unit can be adjusted to a corresponding light adjusting unit according to actual needs, which is convenient to use.

With continued reference to fig. 3, the adjustment body further comprises a total light transmission unit 105, the total light transmission unit 105 is circular in shape, and the diameter of the circle is larger than the diameter of the adjusted light spot 102. It is noted that ideally, a light transmittance of 100% can be achieved when the diameter of the circular full light-transmitting unit 105 is equal to the diameter of the adjusted light spot 102, but considering the existence of system errors, the diameter of the circular full light-transmitting unit 105 is set to be larger than the diameter of the adjusted light spot 102.

In other embodiments of the present embodiment, the shape of the total light transmission unit 105 may be other than a circular shape, and the present embodiment is not particularly limited to this, as long as the light spot can be ensured within the range of the total light transmission unit 105.

With reference to fig. 3, in the using process, the driving portion drives the adjusting body to move, so that the adjusted light spot 120 gradually moves from the first position shown by the solid line circle frame to the second position shown by the dotted line circle frame, for example, the rotation angle of the adjusting body in the using process is set to 20 °, the adjusting body is directly driven to rotate by the motor, the number of steps of one rotation of the motor is 3000, and in addition, as can be seen from the above description, the light adjusting range span of each light adjusting unit is 10%, and the light transmittance adjusting resolution a is 10%/[ (20/360) × 3000] ═ 0.06%.

In this embodiment, a straight line perpendicular to the first direction X is a reference line, and the plurality of grooves may have the same width on any one of the reference lines penetrating through the light adjusting unit.

For example, fig. 4 is a schematic structural diagram of a light modulation unit according to an embodiment of the present invention. In order to avoid the unclear structure of fig. 4 caused by too many reference lines, fig. 4 shows a reference line in the form of a dashed straight line, and as shown in fig. 4, the reference line is referred to as a first reference line 103, the first reference line 103 penetrates through the light adjusting unit, and the widths of the grooves 101 in the light adjusting unit are equal on the first reference line 103. It should be noted that the width of the groove 101 on the first reference line 103 is the length of the intersection of the groove 101 and the first reference line 103 in the extending direction of the first reference line 103.

Optionally, a straight line perpendicular to the first direction X is a reference line, and penetrates through any one of the reference lines of the light adjusting unit, a midpoint of the light adjusting unit is a first center, the width of the groove 101 is equal to the distance between the midpoint and the first center, the center is an inflection point, and the width of the groove 101 is first decreased and then increased in the extending direction of the reference line.

For example, fig. 5 is a schematic structural diagram of another light modulation unit provided in the embodiment of the present invention. In order to avoid the unclear structure of fig. 5 caused by too many illustrated reference lines, a reference line is illustrated in a dashed straight line manner in fig. 5, as shown in fig. 5, the reference line is referred to as a second reference line 104, and with continuing reference to fig. 5, the second reference line 104 penetrates through the light adjusting unit, on the second reference line 104, the center of the light adjusting unit is an O point, the width of the groove 101 with the same distance as the O point is equal, and with the O point as an inflection point, the widths of the grooves 101 in the light adjusting unit are first decreased and then increased in the extending direction of the second reference line 104. With continued reference to fig. 5, the light adjusting unit includes a first groove 11, a second groove 12, a third groove 13, a fourth groove 14, a fifth groove 15, a sixth groove 16, a seventh groove 17, an eighth groove 18, a ninth groove 19, a tenth groove 20, and an eleventh groove 21, the first groove 11 to the eleventh groove 21 are arranged in this order, taking the width of the first groove 11 on the second reference line 104 as a, the width of the second groove 12 on the second reference line 104 as B, the width of the third groove 13 on the second reference line 104 as C, the width of the fourth groove 14 on the second reference line 104 as D, the width of the fifth groove 15 on the second reference line 104 as E, the width of the sixth groove 16 on the second reference line 104 as F, the width of the seventh groove 17 on the second reference line 104 as G, the width of the eighth groove 18 on the second reference line 104 as H, the width of the ninth groove 19 on the second reference line 104 as I, the width of the tenth groove 20 on the second reference line 104 is J, and the width of the eleventh groove 21 on the second reference line 104 is K, then a > B > C > D > E > F, and F < G < H < I < J < K.

It should be noted that fig. 5 illustrates a position of the adjusted spot 120 where the energy of the light that is not adjusted is gaussian in the circular area of the adjusted spot 120, but has good symmetry. When the light adjusting unit shown in fig. 5 is used to adjust the transmittance of light, in order to ensure that the uniformity of light passing through the adjusting body is changed little, the light transmittances of the two side areas of the first axis CD and the light transmittances of the two side areas of the second axis AB in the circular area where the adjusted light spot 120 is located need to be consistent. For the regions on both sides of the first axis CD, since the light transmittance is linearly increased, the influence of the adjusting body on the light uniformity can be reduced by changing the light transmittance adjusting range of the groove 101 per unit length in the first direction X. For the regions on both sides of the second axis AB, the light transmittances of the regions on both sides of the second axis AB can be made the same by adjusting the width of the groove 101 as described above. It is understood that in the light adjusting unit having the structure shown in fig. 5, the center of the adjusted spot 102 needs to coincide with the midpoint of the light adjusting unit on the reference line.

In summary, the arrangement of the groove width in fig. 5 reduces the influence of the adjustment body on the static uniformity, the integral uniformity and the pupil uniformity of the optical system, thereby maintaining the original static uniformity, integral uniformity and pupil uniformity of the optical system, and improving the accuracy of the illumination system using the adjustment body.

Illustratively, the following table 1 is a test result of uniformity of light provided by an embodiment of the present invention. Measured when the light has not passed through the light transmittance adjusting means. Table 2 below shows the results of testing the uniformity of still another light provided by the embodiments of the present invention. The light transmittance adjusting device is characterized in that the adjusting body of the light transmittance adjusting device comprises four light adjusting units which are similar to the structure of the adjusting body shown in fig. 3, and different from fig. 3, the three light adjusting units of the adjusting body except the full light transmitting unit 105 adopt the arrangement mode of the width of the groove 101 in fig. 5, namely, on a reference line which is vertical to the first direction X and penetrates through the corresponding light adjusting unit, the widths of the grooves 101 in the light adjusting unit are firstly reduced and then increased by taking the middle point of the light adjusting unit as an inflection point. As can be seen from tables 1 and 2, after passing through the light transmittance adjusting device, the static uniformity, the integral uniformity, and the pupil uniformity of the light pass through the light transmittance adjusting device, which do not change much, and the original optical characteristics are maintained, which indicates that the light transmittance adjusting device has little influence on the light uniformity. Specifically, fig. 6 is a simulation result of static uniformity after light passes through the adjustment body. FIG. 7 is a simulation of the integrated uniformity after light has passed through the conditioning body. FIG. 8 is a simulation result of pupil uniformity after light passes through an adjustment body. Fig. 6 to 8 further illustrate that the light transmittance adjusting means has a small influence on the light uniformity.

TABLE 1

Static uniformity	Integral uniformity	Pupil uniformity
			0.83％	0.46％	1.63％

TABLE 2

Fig. 9 is a schematic structural diagram of another adjustment body according to an embodiment of the present invention. As shown in fig. 9, the adjusting body includes a substrate 110 and at least one light adjusting unit, the light adjusting unit includes a plurality of grooves 101 formed on the substrate 110 and distributed at equal intervals, the grooves 101 extend along the first direction X, and the adjusted light spots 102 fall on the region where the light adjusting unit is located, along the first direction X, the width of the grooves 101 gradually increases. Specifically, at least one light adjusting unit includes fourth light adjusting unit 124, follows first direction X, in fourth light adjusting unit 124 the width of recess 101 increases gradually from zero to adjacent recess 101 communicates.

It should be noted that the adjusting body in fig. 9 only includes one light adjusting unit, so that the length range of the light adjusting unit in the first direction X is greater than 0 and smaller than the circumference of the substrate 110. In addition, the light transmittance range can be adjusted to 0-100% according to actual needs, and continuous adjustment of the light transmittance between 0-100% is realized. In other embodiments of the present embodiment, the light transmittance range may be adjusted in other ways, for example, the movement speed of the adjusting body is reduced.

With continued reference to fig. 9, the substrate 110 is circular in shape, and the first direction X is an extending direction of a side of the circular shape. It should be noted that the shape of the substrate 110 may also be other shapes than a circle, which is not specifically limited in this embodiment, and it should be noted that the structure of the groove 101 changes correspondingly with the change of the shape of the substrate 110.

Exemplarily, fig. 10 is a schematic structural diagram of another adjustment body provided in an embodiment of the present invention. As shown in fig. 10, the substrate 110 has a rectangular shape, and the first direction X is an extending direction of a long side of the rectangular shape.

It should be noted that although the structure of the groove 101 varies with the shape of the substrate 110, the light adjusting principle and the arrangement mode are the same as those of the circular substrate 110, and are not described herein again.

Fig. 11 is a schematic structural diagram of an illumination system according to an embodiment of the present invention. As shown in fig. 11, the lighting system 2 includes the light transmittance adjusting apparatus 1 according to any embodiment of the present invention.

Illustratively, the illumination system 2 may be an illumination system of a lithography machine. In other embodiments of this embodiment, the lighting system 2 may also be a lighting system of another device, which is not specifically limited in this embodiment.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.