阅读说明：本技术 调制用户界面发光元件的照度水平 (Modulating illumination levels of user interface light emitting elements ) 是由 B·H·尼兹特洛伊 于 2019-08-28 设计创作，主要内容包括：用于电气设备的用户界面的发光元件的照度水平由处理器控制,该处理器用脉宽调制(PWM)或其他类型的控制信号驱动发光元件,该脉宽调制(PWM)或其他类型的控制信号基于以下来计算：a)与将由人类观察者感知的发光元件的期望时变照度水平对应的信号,以及b)实际照度水平与由人类眼睛感知的所得照度水平之间的非线性灵敏度关系,其中该对应信号包括递增的基于正弦的斜坡函数和递减的基于正弦的斜坡函数。(The illumination level of a light emitting element for a user interface of an electrical device is controlled by a processor that drives the light emitting element with a Pulse Width Modulation (PWM) or other type of control signal that is calculated based on: a) a signal corresponding to a desired time-varying illumination level of the light-emitting element to be perceived by a human observer, and b) a non-linear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye, wherein the corresponding signal comprises an increasing sinusoidal-based ramp function and a decreasing sinusoidal-based ramp function.)

1. A method of controlling an illumination level of a light emitting element (1028) for a user interface of an electrical device (1000), the method comprising:

storing, by a processor (1022), information defining a signal corresponding to a desired time-varying illumination level of the light-emitting element to be perceived by a human observer, wherein the corresponding signal comprises an increasing sinusoidal-based ramp function and a decreasing sinusoidal-based ramp function;

calculating, by the processor, a time-varying control signal based on the corresponding signal and a non-linear sensitivity relationship between an actual illumination level and a resulting illumination level perceived by a human eye; and

causing, by the processor, the light emitting element to be illuminated according to the calculated time-varying control signal.

2. The method of claim 1, wherein the corresponding signal is periodic and consists of a plurality of time periods.

3. The method of claim 1, wherein the corresponding signal comprises:

a low level value, the increasing sinusoidal-based ramp function increasing from the low level value to a high level value, and the decreasing sinusoidal-based ramp function decreasing from the high level value to the low level value.

4. The method of claim 1, wherein the non-linear sensitivity relationship comprises a relationship between luminance and psychological brightness.

5. The method of claim 1, wherein the calculated time-varying control signal is calculated by converting the corresponding signal using a compensation function, wherein the compensation function is based on the non-linear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye, and comprises:

if it is notThen

If it is notThen

Wherein

Y is the calculated time-varying control signal; and is

And L is the corresponding signal.

6. The method of claim 1, wherein the increasing ramp function and the decreasing ramp function vary with time t in a manner proportional to:

for the

7. The method of claim 1, wherein the light emitting element (1028) comprises one of a light emitting diode or a light emitting surface.

8. The method of claim 1, wherein the stored information comprises a formula for calculating the corresponding signal.

9. The method of claim 1, wherein the stored information comprises a plurality of discrete sample values representing a time ordering of the corresponding signal.

10. A system for controlling an illumination level of a light emitting element (1028) for a user interface of an electrical device, the system comprising:

a processor (1022); and

a memory in communication with the processor, the memory storing instructions that, when executed by the processor, cause the system to:

storing information defining a signal corresponding to a desired time-varying illumination level of the light-emitting element to be perceived by a human observer, wherein the corresponding signal comprises an increasing sinusoidal-based ramp function and a decreasing sinusoidal-based ramp function;

calculating a time-varying control signal based on the corresponding signal and a non-linear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye; and

causing the light emitting elements to be illuminated according to the calculated time-varying control signal.

11. The system of claim 10, wherein the corresponding signal is periodic and is comprised of a plurality of time periods.

12. The system of claim 10, wherein the corresponding signal comprises:

a low level value, the increasing sinusoidal-based ramp function increasing from the low level value to a high level value, and the decreasing sinusoidal-based ramp function decreasing from the high level value to the low level value.

13. The system of claim 10, wherein the non-linear sensitivity relationship comprises a relationship between luminance and psychological brightness.

14. The system of claim 10, wherein the calculated time-varying control signal is calculated by converting the corresponding signal using a compensation function, wherein the compensation function is based on the non-linear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye, and comprises:

if it is notThen

If it is notThen

Wherein

Y is the calculated time-varying control signal; and is

And L is the corresponding signal.

15. The system of claim 10, wherein the increasing ramp function and the decreasing ramp function vary with time t in a manner proportional to:

for the

Technical Field

The present disclosure relates generally to electrical device user interfaces and, more particularly, to such user interfaces that include light emitting elements, such as Light Emitting Diodes (LEDs).

Background

The light-emitting elements of the user interface of the electrical device may be used to communicate one or more aspects to the consumer regarding the operational status of the device. In other words, the illumination level of the light emitting element indicates the operating state of the electrical device. In the case of LEDs, one typical method for adjusting the LED illumination level is to turn the LED on or off or by flashing the LED. For some consumers, such sudden changes in the illumination level of the light emitting elements may be uncomfortable.

Disclosure of Invention

One aspect of the invention relates to a system for controlling an illumination level of a light emitting element of a user interface for an electrical device, the electrical device comprising a processor and a memory in communication with the processor, the memory for storing instructions that, when executed by the processor, cause the system to: information is stored defining a signal corresponding to a desired time-varying illumination level of the light-emitting element to be perceived by a human observer, wherein the corresponding signal comprises an increasing sinusoidal-based ramp function and a decreasing sinusoidal-based ramp function. The stored instructions, when executed by the processor, further cause the system to calculate a time-varying control signal based on the corresponding signal and a non-linear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye; and causing the light emitting element to be illuminated in accordance with the calculated time-varying control signal.

Another aspect of the present disclosure relates to a method of controlling an illumination level of a light emitting element of a user interface for an electrical device. The method includes storing, by a processor, information defining a signal corresponding to a desired time-varying illumination level of a light-emitting element to be perceived by a human observer, wherein the corresponding signal includes an increasing sinusoidal-based ramp function and a decreasing sinusoidal-based ramp function. The method further includes calculating, by the processor, a time-varying control signal based on the corresponding signal and a non-linear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye; and causing, by the processor, the light emitting element to be illuminated according to the calculated time-varying control signal.

Another aspect of the present disclosure relates to a method of controlling an illumination level of a light emitting element of a user interface for an electrical device. The method includes storing, by a processor, a Pulse Width Modulation (PWM) control signal calculated based on stored information defining a signal corresponding to a desired time-varying illumination level of a light-emitting element to be perceived by a human observer and a non-linear sensitivity relationship between an actual illumination level and a resulting illumination level perceived by a human eye, wherein the corresponding signal includes an increasing sinusoidal-based ramp function and a decreasing sinusoidal-based ramp function. The method also includes driving, by the processor, the light emitting element according to the stored control signal.

Drawings

So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of embodiments of the disclosure, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments that are within the scope of the present disclosure and are therefore not to be considered limiting, for the disclosure may admit to other equally effective embodiments, wherein:

FIG. 1 illustrates three example Pulse Width Modulated (PWM) control signals for a light emitting element according to the principles of the present disclosure;

FIG. 2A illustrates a PWM signal having a linearly increasing duty cycle in accordance with the principles of the present disclosure;

FIG. 2B illustrates how brightness of a light emitting element controlled with the PWM signal of FIG. 2A is perceived according to the principles of the present disclosure;

FIG. 3 illustrates a non-linear relationship between luminance and psychological brightness in accordance with the principles of the present disclosure;

FIG. 4A illustrates a calculated PWM signal based on a linearly increasing ramp function and the non-linear relationship of FIG. 3 in accordance with the principles of the present disclosure;

FIGS. 4B and 4C illustrate linear increasing and decreasing ramp functions, respectively, in accordance with the principles of the present disclosure;

FIG. 5 illustrates a subjective brightness perception graph of a respiratory luminescent user interface element according to the principles of the present disclosure;

FIGS. 6A and 6B illustrate a sinusoidal-based increasing ramp function and a sinusoidal-based decreasing ramp function, respectively, in accordance with the principles of the present disclosure;

FIGS. 7A and 7B illustrate scaled versions of the graphs of FIGS. 6A and 6B, respectively, in accordance with the principles of the present disclosure;

FIG. 8A illustrates a calculated PWM duty cycle signal based on the sinusoidal-based incremental ramp function of FIG. 7A and the non-linear relationship of FIG. 3, in accordance with the principles of the present disclosure;

FIG. 8B illustrates a calculated PWM duty cycle signal based on the sinusoidal-based incremental ramp function of FIG. 7B and the non-linear relationship of FIG. 3 in accordance with the principles of the present disclosure;

FIG. 9 illustrates a variation of the graph of FIG. 5 in accordance with the principles of the present disclosure; and is

Fig. 10A-13 illustrate an electrical device incorporating a light-emitting user interface element in accordance with the principles of the present invention.

Detailed Description

As described above with respect to the light emitting elements of the user interface of the electrical device, turning the LEDs on and off to flash may be uncomfortable for some consumers. It is believed that a more gradual change in the illumination level of the LEDs is more pleasing to some consumers. An embodiment in accordance with the principles of the present disclosure contemplates modulating the illumination level of the LEDs in a manner that is perceived by the human eye as substantially sinusoidal. As described more fully below, implementations may include using a combination of a human eye compensation formula and a harmonic-natural-sinusoidal function.

Although the following discusses one or more example electrical devices, they are provided by way of example only to assist in understanding the principles of the present disclosure and are not intended to limit the interpretation or scope of the appended claims. Embodiments in accordance with the principles of the present disclosure include a variety of light emitting elements such as, for example, LEDs, organic LEDs (oleds), and illuminated surfaces. Modulating the illumination level of the light emitting element may include turning the element on, increasing the illumination level, maintaining the illumination level, decreasing the illumination level, and turning the element off. As explained in more detail below, the PWM signal can be used to control the illumination level of the light emitting elements; however, one of ordinary skill will readily recognize that signals with varying voltages (discrete or analog) may also be used to vary the illumination level of the light-emitting elements. Further, the user interface of the electrical device may comprise more than one light-emitting element, each light-emitting element conveying information about a respective status of a different operating characteristic of the electrical device.

As described above, to control the illumination level of the LED, the LED may be driven by a Pulse Width Modulated (PWM) signal, such as, for example, a Pulse Width Modulated (PWM) signal generated by a microcontroller or similar device. Fig. 1 shows three different PWM signals 102, 104, 106. Each signal is periodic with a period 108 of T. In each period, there is a portion 110t_H(wherein the signal has V_CCVoltage level 120) and portion 112t_L(where the signal has a voltage level 118 of about 0 volts). Voltage level V_CCSufficiently higher than the forward voltage of the LED but low enough to limit the current flowing through the LED in order to prevent damage to the LED. t is t_HThe quotient/T defines the duty cycle of the PWM signal. The duty cycle "k" of the PWM corresponds linearly to the illumination level of the LED and can be expressed as a fraction between 0 and 1 or an equivalent percentage between 0% and 100%. Thus, signal 102 has a "k" 122 equal to 10%, and the illumination level of the LED driven by signal 102 will be at V at that LED_CC10% of the illumination level in the case of continuous or DC signal driving. Signal 104 has a duty cycle k 124 of 50% and signal 106 has a duty cycle k 126 of 90%.

Typically, for PWM signals used to drive LEDs, the switching frequency is so high (i.e., the period T is so short) that the individual oscillations of the illumination level are not perceived by the human eye. The LEDs are perceived as emitting light continuously at a desired illumination level. The minimum speed at which the LED oscillates visible to the human eye varies from person to person. However, a minimum switching frequency of 50Hz or 50 times per second may be typical.

Fig. 2A depicts a graph of a line 202 of how the duty cycle of the PWM signal varies over time. In particular, the depicted duty cycle increases from 0 to 1 or from 0% to 100% in a linear fashion. Based on the above discussion, the illumination level of the LED driven by this PWM signal should also increase in a linear manner with the same slope as line 202. However, fig. 2B shows how the human eye perceives an increasing luminance level of the LED driven by the PWM signal having the varying duty cycle of fig. 2A. Curve 204 indicates the subjective brightness perception of the human eye, which curve 204 does not match line 202. Thus, a user interface with a change in a linearly varying PWM signal is not perceived by the human eye as expected to vary in a linearly varying manner, but rather the human eye treats the increasing illumination level of the LED as varying in a non-linear manner.

The brightness of an object is its absolute intensity. Brightness is the perceived brightness of an object, which depends on the brightness of the surrounding environment. Brightness and brightness may differ because human perception of illumination levels is sensitive to brightness contrast rather than absolute brightness. Brightness is thus a visually perceived attribute, where the light source appears to be radiating or reflecting light. Brightness is the perception caused by the brightness of a visual object and may be referred to as psycho-luminance in the following description. An embodiment in accordance with the principles of the present invention accounts for the subjective perception of the human eye by relying on a compensation function based on studies by the CIE (International Commission on Illumination), which relates brightness to psychological brightness. The compensation function is used to adapt the controlled illumination level of a light emitting element, such as an LED, to the non-linear sensitivity of the human eye. The CIE study correlated luminance values Y varying from 0 to 1 with psychometric luminance values L varying from 0 to 100 and depicted by graph 302 of fig. 3. The graph of fig. 3 is calculated according to the following equation:

if it is notThen 903.3. Y

If it is notThen

In the above equation and subsequent equations, Y varies from 0 to 1 for a particular light emitting element, where the value "1" corresponds to the luminance level of that particular light emitting element driven by a PWM control signal having a duty cycle of 100%, for example. In accordance with the principles of the present disclosure, a compensation function is defined as the inverse of the above equation that transforms or converts L-values to Y-values, and is defined as:

if it is notThen

If it is notThen

In operation, the value of L may be defined such that the illumination level of the LEDs is perceived by the human eye in a desired manner. Based on these L values, a PWM or other type of signal for controlling the illumination level of the LEDs may be determined. One such example is illustrated in fig. 4A and 4B. In this example, a value of L ═ 100 corresponds to a value of Y equal to "1", which also corresponds to a duty cycle of 100%. The value of L ═ 0 also corresponds to the value of Y equal to 0, which also corresponds to a duty cycle of 0%. In fig. 4B, the psychological brightness or subjective brightness perception L of the human eye is defined by the graph 404 as increasing linearly over time. Using the compensation function described above, the changing duty cycle of a PWM or other type of signal that controls the illumination level of the LED can be calculated. For a given value L (t), a corresponding value y (t) may be calculated, having values between 0 and 1, inclusive. The value of y (t) that varies between 0 and 1 is equivalent to the PWM duty cycle k (t), which also varies between 0 and 1 (i.e., between 0% and 100%). In fig. 4A, the graph 402 corresponds to a compensation function applied to the graph 404 of fig. 4B (i.e., the symmetric luminance value L of the graph 404 of fig. 4B is converted to the luminance value Y using the compensation function described above), and thus depicts how, for example, the duty cycle of the PWM signal may be controlled to achieve the perceived linear change in luminance depicted in fig. 4B. Fig. 4C also depicts the perceived linear change in brightness, but in fig. 4C, the value of L decreases from 100 to 0 over time.

A "breathing" lighted user interface is a user interface that periodically alternates between increasing and decreasing illumination levels. Thus, the perceived brightness of the light emitting element also periodically alternates between increasing and decreasing the illumination level. One example is depicted in fig. 5. Graph 502 shows how perceived brightness varies over time. Thus, graph 502 defines a signal corresponding to a desired time-varying illumination level of a light-emitting element to be perceived by a human observer. The graph 502 also shows how there is a sharp transition point 504 between different portions of the graph 502. Due to the presence of the high-level region 510 and the low-level region 512, the signal or graph 502 may be characterized as a non-continuous, increasing ramp function 506 (as shown in fig. 4B) and a decreasing ramp function 508 (as shown in fig. 4C). Using the compensation function described above, for example, the duty cycle of the PWM signal can be calculated to control the illumination level of the LEDs to achieve the desired perceived brightness shown in fig. 5. One further refinement of the signal or plot 502 may be to smooth the transition point 504 in accordance with the principles of the present disclosure.

Instead of L, which varies from 0 to 100 according to the linear ramp of fig. 4B, a sinusoidal based ramp function may be defined, such as, for example:

for the

In the above formula, f (t) follows t/t₀Increasing from 0 to 1 and changing from 0 to 1 as shown in fig. 6A. Similarly, in the above formula, f (t) follows t/t₀Decreasing from 1 to 0 and changing from 1 to 0 as shown in fig. 6B. The sine-based ramp function may be used to derive an increasing sine-based ramp function of L x varying from 0 to 100 and a decreasing sine-based ramp function varying from 100 to 0. Assume a time period t₀The amount of time selected for the value of L increases from 0 to 100, then the incremental sinusoidal-based ramp function of FIG. 7A may be based on t/t for 0 ≦ t₀≤1，L*(t)＝[100*f(t)]To calculate. Additionally, the decreasing sinusoidal-based ramp function of FIG. 7B may be based on a ramp function for 1 ≧ t/t₀≥0，L*(t)＝[100*f(t)]To calculate. The graphs or signals of fig. 7A and 7B correspond to how a designer plans the time-varying illumination levels of the light-emitting elements for perception by a human observer. In other words, the information in the graphs of fig. 7A and 7B defines respective signals corresponding to desired time-varying illumination levels of the light-emitting elements to be perceived by a human observer. However, the control signal for controlling the actual brightness or illumination level of the light emitting elements will be different from the signals of fig. 7A and 7B, because as shown in fig. 3, there is the above-described non-linear sensitivity relationship between the actual illumination level and the resulting illumination level as perceived by the human eye.

As described above with respect to the linear ramps of fig. 4B and 4C, the compensation function may be used to calculate an appropriate PWM signal or other type of control signal to control the illumination level of the LEDs to achieve a desired perception of the brightness of the LEDs by the consumer. As also described above, the compensation function may be used to transform the value of the signal corresponding to the desired varying illumination level that the human eye will perceive. The signal or graph resulting from this conversion corresponds to the luminance value Y of how the illumination level of the light emitting element will actually be controlled. Based on the resulting signal or graph of the luminance value Y, the processor or microcontroller may generate PWM control signals, e.g., at varying duty cycles, to achieve the appropriate actual illumination level of the light-emitting elements. Fig. 8A and 8B depict duty cycle values corresponding to implementing the sinusoidal-based ramp functions of fig. 7A and 7B, respectively. For a given value L (t), in fig. 7A or 7B, the corresponding value y (t) may be calculated using the compensation functions listed above, such that the corresponding value y (t) has a value between 0 and 1 inclusive. Thus, a value of y (t) that varies between 0 and 1 is equivalent to the PWM duty cycle k (t), which also varies between 0 and 1 (i.e., between 0% and 100%).

Fig. 9 depicts the result of using an increasing and decreasing sine-based ramp function instead of the linear ramp function in the graph of fig. 5. As shown, the transition point 904 is smoother than the sharp transition point 504 of fig. 5. Combining the above compensation function with a sinusoidal based ramp function allows calculating a suitable duty cycle of the PWM signal or other control signal, which will enable the brightness of the LED to be perceived in a desired manner. The illumination level Y of the LED is still calculated according to:

if it is notThen

If it is notThen

However, in the above equation, during the increasing or decreasing ramp portion of the graph or signal 902, the values of L (t) are those of the sinusoidal-based ramp function discussed above in fig. 7A and 7B, where:

for 0 ≦ t/t₀≤1，

In graph 902 of fig. 9, there is a time period t corresponding to a period in which the duty cycle of the corresponding PWM signal will remain equal to about "zero" such that the LED is perceived to be off₁. At a time period t₁During this period, L (t) is 0. For example, the time period t₁And may vary from 0 seconds to hundreds of milliseconds. There is also a time period t corresponding to the time period in which the corresponding PWM signal will remain equal to about 100% so that the LED is perceived as being fully lit₂. At a time period t₂During this period, L × t is 100. For example, the time period t₂And may vary from 0 seconds to hundreds of milliseconds. Furthermore, t₁And t₂The values of (a) may be different or they may be the same. In the graph 902, there is also a time period t corresponding to a time period in which the corresponding PWM signal will transition from the off state to the fully on state₀. In graph 902, there is also a corresponding PWM signal thereinThe time period t corresponding to the time period for which the signal will transit from the fully lit state to the off state₃. Time period t₀And a time period t₃May be equal to each other or may be different. t is t₁And t₂Can also be configured as a relative time period, such as, for example, t₁(or t)₂) Is (0.8 × t)₀)。

As some examples, signal 902 may have a t equal to 200ms₀T equal to 0ms₁T equal to 1000ms₂And t equal to 1500ms₃See fig. 12. As another example, t of waveform 902₀And t₃May be equal to 1500ms, t₂May be equal to 40ms, and t₁May be equal to 4000ms, see fig. 12. As another example, waveform 902 may have a t equal to 0ms₁And t₂And t equal to 400ms₀And t₃See fig. 11A. However, in another exemplary waveform 902, t₀And t₃May be equal to 300ms, e.g. t₁May be equal to 90ms, and t₂Can be equal to 700ms, see fig. 11B. In an example waveform 902 without an increasing sinusoidal-based ramp, t₂May be a relatively long period of time, t₃Can be equal to 300ms, see fig. 13.

A device operating in accordance with the principles of the present disclosure may include a processor and a memory in communication with the processor, the memory storing instructions executable by the processor. Further, the instructions, when executed by the processor, cause the device to store information defining a signal corresponding to a desired time-varying illumination level of the light-emitting element to be perceived by a human observer, wherein the corresponding signal includes an increasing sinusoidal-based ramp function and a decreasing sinusoidal-based ramp function. The instructions, when executed, further cause the apparatus to calculate a time-varying control signal based on the corresponding signal and a non-linear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye, and drive the light emitting elements to be illuminated in accordance with the calculated time-varying control signal. Alternatively, the time-varying control signal may be calculated by one or more systems separate from the device. Once the time-varying control signal is calculated, it may be stored in a memory of the device. For example, the time-varying control signal may be stored as a look-up table comprising time-ordered discrete sample values of the calculated time-varying control signal. The processor of the device may read the values from the look-up table and then drive the illumination level of the light emitting elements of the device according to the time-varying control signal.

Fig. 10A illustrates an example electrical device that can include one or more light-emitting elements operating in accordance with the principles of the present disclosure. The example razor 1000 of fig. 10A may include a luminous heating indicator 1001 and a luminous power indicator 1002. In operation, the two indicators 1001, 1002 may operate individually or in synchronization with each other, and may vary in color and illumination levels to communicate the operational status of the razor 1000 to a user.

Fig. 10B is a block diagram of functional elements of razor 1000 or other device that can control light emitting elements of a user interface according to the principles of the present disclosure. Other functional elements of the razor 1000 not related to the light emitting element are omitted from fig. 10B for clarity and brevity.

Razor 1000 may include a microcontroller 1020 or similar hardware that may retrieve data from a data storage device 1026, store data in the data storage device 1026, and retrieve executable instructions from the data storage device 1026. Microcontroller 1020 also includes a processor 1022 or similar circuitry that may execute executable instructions or initiate executable operations. In particular, processor 1022 may communicate with PWM drive circuitry 1024 to generate PWM control signals 1027. PWM control signal 1027 drives light emitting element 1028 such that the illumination level of light emitting element 1028 varies according to the PWM control signal.

One of the executable operations that processor 1022 may initiate is to store information defining a signal corresponding to a desired time-varying illumination level of a light-emitting element to be perceived by a human observer. As described above, the signals or graphs of fig. 5 or 9 correspond to the desired perceived illuminance behavior of the light-emitting element 1028 that the designer of the device 1000 wants to achieve. The signals of fig. 5 or 9 are not limited to actual PWM signals or other types of control signals used to drive the light-emitting element 1028, but rather represent how the human eye will perceive the illumination of the light-emitting element 1028 when the light-emitting element 1028 is driven with the appropriate PWM control signals or other types of control signals. The stored information defining the signal corresponding to the desired time-varying illumination level of the light-emitting element to be perceived by a human observer may be configured in a variety of ways. For example, the information may be a mathematical function describing a graph such as fig. 5 or fig. 9, and may be stored in and retrieved from data storage 1026. In such a case, processor 1022 or a similar component may use a mathematical function to calculate the value of the corresponding signal. Alternatively, the stored information may be a plurality of discrete samples, e.g., corresponding to instantaneous values representing the graphs of fig. 5 or 9, and may be stored in and retrieved from the data storage 1026 by the processor 1022. The stored information may represent a single period of a periodic signal, and the sample values may be time-ordered such that the processor 1022 may sequentially retrieve the various values of the stored information to determine the value of the corresponding signal. The sampled values may represent the approximate profile of a graph or signal (e.g., the graph or signal of fig. 9), but may be scaled up or down, if desired, by processor 1022. In the particular embodiment described above, the corresponding signal includes an increasing sine-based ramp function and a decreasing sine-based ramp function.

Another executable operation that the processor may initiate is to calculate a time-varying control signal based on: a) a corresponding signal defined by the stored information, and b) a non-linear sensitivity relationship between the actual illumination level and the resulting illumination level as perceived by the human eye. Fig. 3 shows an example of this type of non-linear sensitivity relationship. The horizontal axis represents the actual or physical illumination level of the light-emitting element, and the vertical axis represents how the human eye perceives different illumination levels. In the above example, the compensation function is derived from the relationship shown in fig. 3 and used to calculate the control signal. Because the corresponding signal defined by the stored information is time-varying (examples are depicted by the graphs of fig. 5 or fig. 9), the signal has multiple individual values that may be labeled L x (t), where "t" represents a discrete-time value. The compensation function may be used to calculate the luminance value y (t) corresponding to the value L (t). These luminance values y (t) may then be converted into corresponding duty cycle values k (t) for the PWM control signal or corresponding voltage values v (t) for the time-varying voltage control signal. An ordered series of values k (t) or v (t) defines a calculated control signal that varies with time available to drive the light-emitting element 1028.

Thus, another of the executable operations that processor 1022 may initiate includes causing the light emitting element to be illuminated in accordance with the calculated time-varying control signal such that a human observer perceives an illumination level of the light emitting element 1028 that generally corresponds to the corresponding signal. The processor 1022 may be configured to directly drive the light-emitting element 1028, or may be configured to control or communicate with individual PWM drive circuitry 1024 to generate a PWM signal having appropriate voltage levels and timing characteristics. The processor 1022 may also be configured to control or communicate with other drive circuitry (not shown) to generate control signals (e.g., the varying voltage signal v (t) described above) having appropriate voltage levels and timing characteristics.

Fig. 11A shows an example of how different light-emitting elements 1001 and 1002 can operate. The horizontal timeline 1104 provides an example graph of information defining a signal corresponding to a desired time-varying illumination level of the heating indicator 1001 to be perceived by a human observer, and the horizontal timeline 1106 provides an example graph of information defining a signal corresponding to a desired time-varying illumination level of the power indicator 1002 to be perceived by a human observer. Once the razor 1000 is turned on (1108), a warm-up period 1110 may begin and may last, for example, for about 2 seconds. During this time, power indicator 1002 is fully illuminated and heating indicator 1001 breathes at a rate of, for example, about 0.5 seconds. Both the lighted indicator 1001 and the lighted indicator 1002 may remain continuously illuminated when the razor 1000 reaches its ready-to-use state (1112) and its in-use state (1114). When the razor 1000 is turned off, then both the light indicator 1001 and the light indicator 1002 may be turned off. In fig. 11A, a charging dock 1102 is depicted that may be connected with the razor 1000.

Fig. 11B shows how the light indicator 1001 and the light indicator 1002 can be controlled to indicate different operating states of the razor 1000. The horizontal timeline 1150 provides an example graph of information defining a signal corresponding to a desired time-varying illumination level of the heated indicator 1001 to be perceived by a human observer, and the horizontal timeline 1152 provides an example graph of information defining a signal corresponding to a desired time-varying illumination level of the power indicator 1002 to be perceived by a human observer. During a low battery state of charge condition (1148), the heating indicator 1001 is fully illuminated and the power indicator 1001 blinks at a rate of, for example, about 1.0 second.

Fig. 12 shows one example of how the light emitting elements 1001 and 1002 may operate when the razor 1000 is connected to the charging dock 1102. In particular, the charging dock 1102 may include its own light emitting element 1202, which may be a charge indicator. Horizontal timeline 1204 provides an example graph of information defining a signal corresponding to a desired time-varying illumination level of heated indicator 1001 to be perceived by a human observer, and horizontal timeline 1206 provides an example graph of information defining a signal corresponding to a desired time-varying illumination level of power indicator 1002 to be perceived by a human observer. The horizontal timeline 1208 provides an example graph of information defining signals corresponding to desired time-varying illumination levels of the charge indicator 1202 to be perceived by a human observer.

In the example of fig. 12, heating indicator 1001 may remain unlit during all of the periods shown, such as when razor 1000 is placed on a charger (1210), when razor 1000 is charging (1212), and when the razor is fully charged (1214). In accordance with the principles of the present disclosure, a PWM or other type of control signal may be calculated that causes both power indicator 1002 and charge indicator 1202 to operate as a light emitting respiratory user interface. The PWM signal may, for example, cause the illumination levels of both element 1002 and element 1202 to change such that they are perceived as changing, as shown in fig. 9 and horizontal timelines 1206 and 1208. In the example of fig. 12, the respiration rate is about 3 seconds. Fig. 12 also shows that when the razor 1000 is placed on the charging stand 1102, the synchronization pulses can be sent to the processor or controller that generates the PWM control signals for the power indicator 1002, and can also be sent to the processor or controller that generates the PWM control signals for the charge indicator 1202.

Fig. 13 shows that the same light-emitting element can have different colors at different times. In fig. 13, a horizontal timeline 1302 provides an example graph of information defining a signal corresponding to a desired time-varying illumination level of the heating indicator 1001 to be perceived by a human observer, and a horizontal timeline 1304 provides an example graph of information defining a signal corresponding to a desired time-varying illumination level of the power indicator 1002 to be perceived by a human observer. During the time when the user presses the button 1003 to enter the first heating mode (1310), both the lighted indicator 1001 and the lighted indicator 1002 may be fully illuminated and red in color. During the first heating mode (1312), both indicator 1001 and indicator 1002 may remain fully illuminated but yellow in color. During the time when the user presses the button again (1314) to enter the second heating mode, both indicator 1001 and indicator 1002 may remain fully illuminated and yellow in color. However, when the second thermal mode (1316) is reached, the colors of the illuminated light emitting elements 1001 and 1002 may change to red.

The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various aspects of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). Further, while the flow diagrams have been discussed and illustrated with respect to a particular sequence of events, it should be understood that changes, additions, and omissions to the sequence may be made without materially affecting the operation of the disclosure. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

As will be appreciated by those skilled in the art, aspects of the present disclosure may be shown and described herein in any of a number of patentable categories or contexts, including any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof. Accordingly, aspects of the present disclosure may be embodied entirely in hardware, entirely in software (including firmware, resident software, micro-code, etc.) or in a combination of software and hardware implementations that may be collectively referred to herein as a "circuit," module, "" component "or" system. Furthermore, aspects of the present disclosure may take the form of a computer program product embodied in one or more computer-readable media having computer-readable program code embodied thereon.

Any combination of one or more computer-readable media may be utilized. The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer readable storage medium would include the following: a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a suitable optical fiber with a relay, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

Computer program code for performing operations of aspects of the present disclosure may be written in any combination of one or more programming languages, including an object oriented programming language such as JAVA, SCALA, SMALLTALK, EIFFEL, JADE, EMERALD, C + +, CII, vb.net, PYTHON, and the like; conventional program programming languages such as "c" programming language, VISUAL BASIC, FORTRAN 2003, PERL, COBOL 2002, PHP, ABAP; dynamic programming languages such as PYTHON, RUBY, and GROOVY; or other programming language. The program code may execute entirely on the user's computer or device.

Aspects of the present disclosure are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the disclosure. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable instruction execution apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable medium that, when executed, may direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions, when stored in the computer-readable medium, produce an article of manufacture including instructions which, when executed, cause the computer to implement the function/act specified in the flowchart and/or block diagram block or blocks. The computer program instructions may also be loaded onto a computer, other programmable instruction execution apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

Representative embodiments of the present disclosure described above may be described as follows:

A. a method of controlling an illumination level of a light emitting element of a user interface for an electrical device, the method comprising:

storing, by a processor, information defining a signal corresponding to a desired time-varying illumination level of the light-emitting element to be perceived by a human observer, wherein the corresponding signal comprises an increasing sinusoidal-based ramp function and a decreasing sinusoidal-based ramp function;

calculating, by the processor, a time-varying control signal based on the corresponding signal and a non-linear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye; and

causing, by the processor, the light emitting element to be illuminated in dependence on the calculated time-varying control signal.

B. The method of paragraph a, wherein the corresponding signal is periodic and is made up of a plurality of time periods.

C. The method of paragraph a or paragraph B, wherein the corresponding signal comprises:

a low level value, the increasing sinusoidal-based ramp function increasing from the low level value to a high level value, and the decreasing sinusoidal-based ramp function decreasing from the high level value to the low level value.

D. The method of any of paragraphs a-C, wherein the non-linear sensitivity relationship comprises a relationship between luminance and psychological brightness.

E. The method according to any of paragraphs a-D, wherein the calculated time-varying control signal is calculated by converting the corresponding signal using a compensation function, wherein the compensation function is based on the non-linear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye, and comprises:

if it is notThen

If it is notThen

Wherein

Y is the calculated time-varying control signal; and is

And L is the corresponding signal.

F. The method of any of paragraphs a through E, wherein the increasing ramp function and the decreasing ramp function vary over time t in a manner proportional to:

for the

G. The method of any of paragraphs a through F, wherein the light emitting element comprises one of a Light Emitting Diode (LED) or a light emitting surface.

H. The method of any of paragraphs a through G, wherein the stored information includes a formula for calculating the corresponding signal.

I. The method of any of paragraphs a-H, wherein the stored information comprises a plurality of discrete sample values representing a temporal ordering of the corresponding signal.

J. A system for controlling an illumination level of a light emitting element of a user interface for an electrical device, the system comprising:

a processor; and

a memory in communication with the processor, the memory storing instructions that, when executed by the processor, cause the system to:

storing information defining a signal corresponding to a desired time-varying illumination level of the light-emitting element to be perceived by a human observer, wherein the corresponding signal comprises an increasing sinusoidal-based ramp function and a decreasing sinusoidal-based ramp function;

calculating a time-varying control signal based on the corresponding signal and a non-linear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye; and

-causing the light emitting elements to be illuminated according to the calculated time-varying control signal.

K. The system of paragraph J, wherein the corresponding signal is periodic and is made up of a plurality of time periods.

L. the system of paragraph J or paragraph K, wherein the corresponding signal comprises:

a low level value, the increasing sinusoidal-based ramp function increasing from the low level value to a high level value, and the decreasing sinusoidal-based ramp function decreasing from the high level value to the low level value.

The system of any of paragraphs J through L, wherein the nonlinear sensitivity relationship comprises a relationship between luminance and psychological brightness.

N. the system of any of paragraphs J through M, wherein the calculated time-varying control signal is calculated by converting the corresponding signal using a compensation function, wherein the compensation function is based on the nonlinear sensitivity relationship between the actual illumination level and a resulting illumination level perceived by the human eye and comprises:

if it is notThen

If it is notThen

Wherein

Y is the calculated time-varying control signal; and is

And L is the corresponding signal.

O. the system according to any of paragraphs J to N, wherein the increasing ramp function and the decreasing ramp function vary with time t in a manner proportional to:

for the

P. the system of any of paragraphs J through O, wherein the light emitting element comprises one of a Light Emitting Diode (LED) or a light emitting surface.

The system of any of paragraphs J through P, wherein the stored information comprises a formula for calculating the corresponding signal.

R. the system of any of paragraphs J through Q, wherein the stored information comprises a plurality of discrete sample values representing a temporal ordering of the corresponding signal.

S. a method of controlling an illumination level of a light emitting element of a user interface for an electrical device, the method comprising:

storing, by a processor, a Pulse Width Modulation (PWM) control signal calculated based on stored information defining a signal corresponding to a desired time-varying illumination level of the light-emitting element to be perceived by a human observer and a non-linear sensitivity relationship between an actual illumination level and a resulting illumination level perceived by the human eye, wherein the corresponding signal comprises an increasing sinusoidal-based ramp function and a decreasing sinusoidal-based ramp function; and

driving the light emitting element by the processor with the stored PWM control signal.

T. the method of paragraph S, wherein the stored PWM control signal comprises a look-up table.

The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Rather, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as "40 mm" is intended to mean "about 40 mm".

Each document cited herein, including any cross referenced or related patent or patent application and any patent application or patent to which this application claims priority or its benefits, is hereby incorporated by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with any disclosure of the invention or the claims herein or that it alone, or in combination with any one or more of the references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.