TWI786682B - Optical mouse and its control method - Google Patents

Abstract

The present invention relates to an optical mouse and its control method. When the optical mouse operates on the working surface, the optical mouse controls the transmission and reception of the optical signals at a first frame rate. When the optical mouse is lifted away from the work surface, the optical mouse controls the transmission and reception of the optical signals at a second frame rate. The second frame rate is larger than the first frame rate. Then the optical mouse is switched to the higher frame rate to control the transmission and reception of optical signals when the optical mouse is lifted. Thus, more reflection images are obtained relatively, the optical mouse has more information to quickly determine abnormal reflection images. Then the reporting of the abnormal reflection images are prevented to avoid reflecting the abnormal movement track.

Description

Optical mouse and its control method

The invention relates to an optical mouse, especially the technology related to controlling the light-emitting frequency of the optical mouse.

The optical mouse is a common input device used with electronic devices. When the optical mouse is used, it is placed on the work surface and moved. The light emitted by the internal light source of the optical mouse hits the corresponding position on the work surface. The reflected light generated by the corresponding position is reflected into the optical mouse, and then the sensing unit inside the optical mouse captures the image of the corresponding position, and the moving path of the optical mouse is judged by analyzing the image, so as to control the display of the electronic device accordingly The cursor position.

When the user lifts the optical mouse while moving so that the bottom surface is not attached to the work surface (for example, slightly lifted away from the work surface or moved outside the edge of the work surface during use), the light emitted by the light source will follow When the optical mouse is raised, the angle diverges and cannot be focused on one place, and the unfocused light is irradiated on the work surface corresponding to the optical mouse. At this time, the sensing unit is limited by its angle and corresponding position, and the captured The blurred or decreased brightness of the image may easily cause the electronic device to misjudge the movement path of the optical mouse in an instant. Therefore, how to respond effectively to improve the accuracy of judging the movement path when the relationship between the optical mouse and the work surface changes, Become the problem that prior art needs to solve.

In view of this, the present invention aims at changing the control mode when the lifting state of the optical mouse changes, so as to improve the accuracy of judging the moving path of the optical mouse.

In order to achieve the above-mentioned purpose of the invention, the present invention provides a control method of an optical mouse, which includes the following steps: when the optical mouse is operated on a work surface, controlling the emission and reception of optical signals at a first frame rate ; when the optical mouse leaves the work surface, control the emission and reception of light signals at a second frame rate, wherein the second frame rate is greater than the first frame rate; when the optical mouse is at the second frame rate When controlling the emission and reception of optical signals, it is judged whether the optical mouse returns to the work surface, and if so, the optical mouse will switch back to the first frame rate to control the emission and reception of optical signals after a certain time delay. During the specific delay period, the second frame rate is still used to control the transmission and reception of the optical signal.

The present invention also provides an optical mouse for implementing the aforementioned control method, which includes: a casing; a light source, which is arranged in the casing and provides light signals to the outside of the casing; a sensing unit, which is arranged in the casing A reflected light signal in the body and receiving the light signal; a control unit, which is arranged in the casing, and the control unit controls the light source to provide the light signal, wherein the control unit controls the light source to execute the aforementioned control method.

The advantage of the present invention is that by increasing the frame rate of the optical signal controlled when the optical mouse leaves the work surface, the number of captured images can be increased when the optical mouse leaves the work surface, so that the control unit can quickly By judging abnormal images, it is possible to quickly block and report displacements that are not expected by the user, so as to improve user experience.

1: Optical mouse

10: Shell

20: light source

21: light

30: Control unit

40: Sensing unit

50: work surface

T: light cycle

S ₁₁ , S ₁₂ : the first light signal

S ₂₁ , S ₂₂ : the second light signal

t ₁₁ , t ₁₂ : the first time

t ₂₁ , t ₂₂ : second time

Φ ₁₁ , Φ ₁₂ : the first luminous flux

Φ ₂₁ , Φ ₂₂ : Second luminous flux

I ₁₁ , I ₁₂ : first reflection image

I ₂₁ , I ₂₂ : second reflected image

Fig. 1 is a schematic side view sectional view of the optical mouse of the present invention in a non-lifted state; Fig. 2 is a block diagram of some components of the optical mouse of the present invention; Fig. 3 is an implementation state of the optical mouse of the present invention during operation Schematic diagram; Fig. 4 is the timing diagram of light emission when the optical mouse of the present invention is on the working surface; Fig. 5 is the timing diagram of light emission when the optical mouse of the present invention is lifted; Fig. 6 is the judging whether the optical mouse is lifted of the present invention The luminescence timing diagram of the first embodiment; Fig. 7 is the luminescence timing diagram of the second embodiment of judging whether the optical mouse is lifted; Fig. 8 is the third judging whether the optical mouse is lifted of the present invention The light-emitting sequence diagram of the embodiment; FIG. 9 is the light-emitting sequence diagram of the fourth embodiment of judging whether the optical mouse is lifted; FIG. 10 is one of the implementation states of the optical mouse in the non-lifted state of the present invention Figure 11 is a schematic diagram of a side view of the optical mouse of the present invention in a lifted state; Figure 12 is an implementation of the optical mouse of the present invention in a lifted state Figure 13 to Figure 16 are schematic diagrams of the illuminance of each pixel of the reflected image captured by the present invention.

The technical means adopted by the present invention to achieve the intended purpose of the invention are further elaborated below in conjunction with the drawings and embodiments of the present invention, wherein the drawings are simplified for illustrative purposes only, and by describing the relationship between elements and components of the present invention To illustrate the structure or method invention of the present invention, therefore, the elements shown in the drawings are not presented in actual number, actual shape, actual size and actual ratio, and the size Or the size ratio has been enlarged or simplified to provide better illustration, the actual number, actual shape or actual size ratio has been selectively designed and configured, and the detailed component layout may be more complicated.

Please refer to FIG. 1 and FIG. 2 , the optical mouse 1 of the present invention includes a casing 10 , a light source 20 , a control unit 30 and a sensing unit 40 . The light source 20, the control unit 30 and the sensing unit 40 are all arranged in the housing 10, the light source 20 and the sensing unit 40 are electrically connected to the control unit 30, and the light 21 emitted by the light source 20 is directed toward the Outside the casing 10, that is, the light source 20 provides light signals to the outside of the casing 10. When the light 21 hits the working surface 50 placed on the bottom surface of the casing 10, the reflected light is received by the sensing unit 40, And then generate a corresponding reflection image, and judge the moving distance of the optical mouse 1 by the reflection image.

Please refer to FIG. 3 , when the optical mouse 1 is in operation, the optical mouse 1 will operate on or leave the work surface 50 due to the actions of the user. Please refer to FIG. 2, FIG. 4 and FIG. 5. When the optical mouse 1 is operated on the work surface 50, the control unit 30 controls the transmission and reception of optical signals at a first frame rate (as shown in FIG. 4); at the same time, the control unit 30 continues to judge whether the optical mouse 1 leaves the work surface 50 according to the aforementioned reflected image received by the sensing unit 40, if it is judged that the optical mouse 1 leaves the work surface 50, Then the control unit 30 changes to a second frame rate to control the transmission and reception of optical signals (as shown in FIG. 5 ), wherein the second frame rate is greater than the first frame rate, which means that the optical mouse 1 is leaving When the working surface 50 is used to control the light signal at a higher frame rate, relatively speaking, the sensing unit 40 will also receive more of the aforementioned reflected images. Comparing with Fig. 4 and Fig. 5, in the same time length A, the light signal is emitted only once with the first frame rate (Fig. 4) and only one reflection image is obtained, but the For the second frame rate (FIG. 5) for emitting light signals, the light signals are emitted three times to obtain the three reflection images mentioned above. In this way, the control unit 30 will have more information, and can judge that the received reflection image is incorrect in a short period of time. The normal image is blocked, so as to avoid that the trajectory corresponding to the optical mouse 1 includes the aforementioned reflected image received when the optical mouse 1 is lifted.

In one embodiment, when the optical mouse 1 leaves the work surface 50, it is further judged whether the optical mouse returns to the work surface 50, and if so, the control unit 30 delays a certain time before switching back to the first work surface. A frame rate is used to control the emission and reception of the optical signal, and the second frame rate is still used to control the emission and reception of the optical signal within the specified delay time. As mentioned above, when the optical mouse 1 is lifted, more reflection images can be obtained with a higher frame rate, which helps to prevent the return of abnormal use conditions, so when the optical mouse 1 is just lifted When returning to the work surface 50 from the state, the high frame rate still maintained for a short period of time also contributes to the number of reflection images acquired under the state switching, so that the control unit 30 is lifted and returned to the work surface 50 Under the state transition of , there can be more aforementioned reflected images to assist the judgment.

In one embodiment, when the optical mouse 1 is operated on the work surface 50, the control unit 30 further determines whether the optical mouse 1 has a displacement, if it is determined that the optical mouse 1 has a displacement on the work surface 50 Displacement or displacement within a preset time is greater than a threshold, then the control unit 30 maintains the first frame rate to control the transmission and reception of optical signals, if it is judged that the optical mouse 1 is still on the work surface 50 or If the displacement is less than a threshold within the preset time, the control unit 30 controls the transmission and reception of optical signals at a third frame rate, wherein the third frame rate is lower than the first frame rate, so that the optical mouse 1. In a static or near-static state, based on the low demand for judging the movement track, a smaller frame rate is used to control the emission and reception of optical signals to save the optical mouse 1 in this state. energy consumption.

In one embodiment, the first frame rate is selected from a first range, the second frame rate is selected from a second range, and the third frame rate is selected from a third range. In one embodiment, the first range is 9600Hz~15000Hz, the second range is 14000Hz~25000Hz, and the third range is 0~9600Hz.

In one embodiment, whether the optical mouse is lifted can be determined by controlling the magnitude of the emitted light signal. Please refer to FIG. 2 and FIG. 6, the control unit 30 controls the light source 20 to perform at least one lighting period T, and in each lighting period T, the light source 20 emits a plurality of first light signals _S11 and at least one The second optical signal S ₂₁ , wherein the time length for emitting the first optical signal S ₁₁ is a first time t ₁₁ , and the first optical signal S ₁₁ has a first luminous flux Φ ₁₁ , and the second optical signal S is emitted The time length of ₂₁ is a second time t ₂₁ , and the second optical signal S ₂₁ has a second luminous flux Φ ₂₁ . Moreover, the magnitude of the first optical signal _S11 is different from that of the second optical signal _S21 . In one embodiment, the magnitude refers to the optical energy of the optical signal, that is, the product of the luminous flux of the optical signal and the emission time , the luminous energy of the first optical signal S ₁₁ is equal to the product of the first time t ₁₁ and the first luminous flux Φ ₁₁ , and the luminous energy of the second optical signal S ₂₁ is equal to the second time t ₂₁ and the second luminous flux The product of Φ ₂₁ . Please refer to the embodiment shown in Fig. 6, the first luminous flux Φ ₁₁ is equal to the second luminous flux Φ ₂₁ , but since the first time t ₁₁ is greater than the second time t ₂₁ , the first time t ₁₁ and the The product of the first light flux _Φ11 is greater than the product of the second time _t21 and the second light flux _Φ21 , so the magnitude of the first light signal _S11 is different from that of the second light signal _S21 . Please refer to the embodiment shown in Figure 7, the first time t ₁₂ is equal to the second time t ₂₂ , but the first luminous flux Φ ₁₂ is greater than the second luminous flux Φ ₂₂ , so the first time t ₁₂ and the second luminous flux Φ 22 The product of a luminous flux _Φ12 is larger than the product of the second time _t22 and the second luminous flux _Φ22 , so the magnitude of the first light signal _S12 is different from that of the second light signal _S22 . In other embodiments, the first time can also be different from the second time, the first luminous flux can be different from the second luminous flux, but the product of the first time and the first luminous flux can be greater or smaller than the second The product of time and the second luminous flux can correspond to the difference between the magnitude of the first light signal and the magnitude of the second light signal.

Furthermore, in each of the light-emitting periods T, the times and ways of emitting the first light signal and the second light signal may have different implementations. Please refer to the embodiment shown in Figure 6, which is to emit multiple first optical signals _S11 and multiple second optical signals S21 (as shown in Figure ₆ , two first optical signals _S11 and two second optical signals light signal S ₂₁ ), and the first light signal S ₁₁ and the second light signal S ₁₂ are alternately emitted. Please refer to the embodiment shown in Figure 8, which is to emit multiple first light signals _S11 and one second light signal S21 (as shown in Figure ₈ , three first light signals _S11 and one second light signal S ₂₁ ). Please refer to the embodiment shown in Figure 9, which is to emit multiple second light signals S ₂₁ and one first light signal S ₁₁ (as shown in Figure 9, one first light signal S ₁₁ and three second light signals S ₂₁ ).

Please refer to FIG. 1 and FIG. 10 , when the optical mouse 1 is normally placed on the work surface 50 for use, and the light source 20 emits the first light signal _S11 , the corresponding reflected light is received by the sensing unit 40 And generate a first reflected image I ₁₁ ; when the light source 20 emits the second light signal S ₂₁ , the corresponding reflected light is received by the sensing unit 40 to generate a second reflected image I ₂₁ . Since the first light signal _S11 and the second light signal _S21 have different magnitudes, when irradiating the working surface 50, the reflected light corresponding to the first light signal _S11 and the second light signal _S21 There are also different sizes, and the generated first reflected image _I11 and the second reflected image _I21 will have different illumination reference values. Taking Fig. ₁₀ as an example, since the magnitude of the first light signal _S11 is greater than the magnitude of the second light signal S21, the first illuminance reference value of the corresponding first reflection image _I11 generated by default will be greater than the first The second illuminance reference value of the reflection image _I21 . At this time, after calculating the first illuminance reference value of the first reflection image _I11 and the second illuminance reference value of the second reflection image _I21 , a comparison result is obtained. If the comparison result meets the first If the first illuminance reference value of the reflected image I11 is greater than the second illuminance reference value of the second reflected image _I21 , it can be judged that the optical mouse ₁ is placed on the work surface 50 instead of being lifted. state. Even though the contrast of the work surface 50 is relatively high or the texture features of the work surface 50 are not obvious, the optical mouse 1 has different magnitudes from the first light signal _S11 and the second light signal _S21 . The illuminance reference value of the captured reflection image will still be affected by the magnitudes of the first light signal _S11 and the second light signal _S21 , so as to produce a difference in line with the preset result.

Please refer to FIG. 11 and FIG. 12 , when the optical mouse 1 is lifted and not attached to the work surface 50, because the first light signal S ₁₁ and the second light signal S ₂₁ have diverged and have not Reflected light is formed so that the magnitudes of the first light signal _S11 and the second light signal S21 do not affect the illuminance reference values _of the first reflected image _I12 and the second reflected image _I22 , so no matter for In response to the first reflected image I ₁₂ generated by the first light signal S ₁₁ , or the second reflected image I ₂₂ generated in response to the second light signal S ₂₁ , the illuminance reference value only corresponds to the current working surface 50 Or the brightness of the corresponding position in the sky. Therefore, at this time, the comparison result obtained after calculating the first illuminance reference value of the first reflection image _I11 and the second illuminance reference value of the second reflection image _I21 will be similar to each other. The illuminance reference value cannot meet the result that the first illuminance reference value of the first reflected image _I11 is greater than the second illuminance reference value of the second reflected image _I21 , so it can be judged that the optical mouse 1 is currently leaving the work The surface 50 is in a raised state.

The illuminance reference value may refer to an operational value related to the illuminance of all or some pixels in the reflected image, for example, if the illuminance of each pixel in the first reflected image I11 shown in FIG. ₁₀ As shown in Figure 13, if the illuminance of each pixel in the second reflected image I11 shown in Figure ₁₀ is shown in Figure 14, if the illuminance of each pixel in the first reflected image I12 shown in Figure ₁₂ As shown in FIG. 15, if the illuminance of each pixel in the second reflection image _I22 shown in FIG. 12 is as shown in FIG. 16, the illuminance shown in FIGS. to limit the invention.

In one embodiment, the illuminance reference value is the sum of the illuminances of all the pixels of the reflected image, and the comparison result can be the sum of the illuminances of all the pixels of the first reflected image and the sum of the illuminances of all the pixels of the second reflected image. If the difference or ratio of the sum of the illuminances of all pixels is judged to be less than a threshold value, it is judged that the optical mouse is in a raised state. Assuming that the threshold value of the difference is 5000 and the threshold value of the ratio is 5, from the reflection images obtained by the optical mouse 1 in the state of Fig. 1 and Fig. ₁₀ , the values of all pixels of the first reflection image I11 are The sum of the illuminance is 60649 (as shown in Figure 13), and the sum of the illuminance of all pixels of the second reflected image _I21 is 6164 (as shown in Figure 14), then the difference is 54485, and the ratio is 9.84, showing The difference between the total illuminance of the two is quite large, and the comparison result is greater than the preset threshold value, then it is judged that the optical mouse 1 is not in the lifted state; the reflection image obtained by the optical mouse 1 in the state shown in Figure 11 and Figure 12 From the point of view, the sum of the illuminance of all the pixels of the first reflected image I12 is ₁₇₈₄₄ (as shown in FIG. 15 ), and the sum of the illuminance of all the pixels of the second reflected image I22 is 16942 (as shown in FIG. ₁₆ As shown), the difference is 902, and the ratio is 1.05, which shows that the difference between the total illuminance of the two is very small, and the comparison result is less than the preset threshold value, and the optical mouse 1 is judged to be in the raised state.

In one embodiment, the illuminance reference value is the average illuminance value of all pixels in the reflected image, and the comparison result can be the sum of the illuminances of all pixels in the first reflected image and the second reflected image If the difference or ratio of the average illuminance values of all pixels in the image is judged to be less than a threshold value, the optical mouse is judged to be in a raised state. Assuming that the threshold value of the difference is 500 and the threshold value of the ratio is 2, the illuminance of all pixels of the first reflected image I ₁₁ can be seen from the reflection images obtained by the optical mouse 1 in the state shown in Figure 1 and Figure 10 The average value is 6738.78 (as shown in Figure 13), the illuminance average value of all pixels of the second reflection image _I21 is 684.89 (as shown in Figure 14), then its difference is 6053.89, and its ratio is 9.84, showing The difference between the average illuminance of the two is quite large, and the comparison result is greater than the preset threshold value, then it is judged that the optical mouse 1 is not in the lifted state; the reflection diagram obtained by the optical mouse 1 in the state shown in Figure 11 and Figure 12 From the perspective of the image, the average illuminance of all pixels in the first reflected image I12 is _1982.67 (as shown in Figure 15), and the average illuminance of all pixels in the second reflected image I22 is _1882.44 (as shown in Figure 16 As shown), the difference is 100.23, and the ratio is 1.05, which shows that the difference between the average illuminance values of the two is very small, and the comparison result is smaller than the preset threshold value, and the optical mouse 1 is judged to be in the raised state.

In one embodiment, the illuminance reference value may be the sum or average illuminance of some pixels of the reflection image, and the comparison result may be adjusted accordingly.

In one embodiment, the comparison result can be compared with the first optical signal and the second optical signal emitted in adjacent time sequences, or compared with any first optical signal and any second optical signal in the same period, Or compare the first light signal and the second light signal in different periods.

The above description is only an embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as above with the embodiment, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field, Within the scope of not departing from the technical solution of the present invention, when the technical content disclosed above can be used to make some changes or be modified into equivalent embodiments with equivalent changes, but all the content that does not depart from the technical solution of the present invention, according to the technical essence of the present invention Any simple modifications, equivalent changes and modifications made to the above embodiments still fall within the scope of the technical solutions of the present invention.

1: Optical mouse 50: work surface

Claims (20)

A method for controlling an optical mouse, comprising the following steps: when the optical mouse is operated on a work surface, controlling the transmission and reception of light signals at a first frame rate; and when the optical mouse leaves the work surface When the optical mouse controls the transmission and reception of optical signals at a second frame rate, wherein the second frame rate is greater than the first frame rate; when the optical mouse controls the transmission and reception of optical signals at the second frame rate, it is judged Whether the optical mouse returns to the work surface, if so, the optical mouse will switch back to the first frame rate to control the emission and reception of the light signal after a certain time delay. The transmission and reception of optical signals are controlled at the second frame rate. The method for controlling an optical mouse as described in Claim 1, wherein when the optical mouse is operated on the work surface, it is further judged whether the optical mouse has a displacement, and if so, the optical signal is controlled at the first frame rate if not, then control the transmission and reception of optical signals at a third frame rate; wherein the third frame rate is less than the first frame rate. The control method of an optical mouse according to claim 1, wherein the first frame rate is selected from a first range, and the second frame rate is selected from a second range. The control method of an optical mouse as described in Claim 2, wherein the first frame rate is selected from a first range, the second frame rate is selected from a second range, and the third frame rate is selected from a third range . The control method of the optical mouse as described in claim 1, which includes at least one light-emitting period, and when judging whether the optical mouse leaves the work surface, includes the following steps: In each of the light-emitting periods, a first light signal is emitted to obtain a first reflected image, and a second light signal is emitted to obtain a second reflected image, and the magnitude of the first light signal is the same as that of the second light signal. The magnitudes of the two light signals are different; calculating a first illuminance reference value of the first reflected image and a second illuminance reference value of the second reflected image and obtaining a comparison result; and according to the comparison result It is judged whether the optical mouse is away from the work surface. The control method for an optical mouse as claimed in item 5, wherein the first reference value of illumination and the second reference value of illumination are respectively obtained in different lighting periods. The control method of an optical mouse as claimed in claim 5 or 6, wherein the second reflection image and the first reflection image are adjacent in time sequence. The control method of an optical mouse as described in Claim 5, wherein in each light-emitting period, the first light signal and the second light signal are respectively emitted multiple times, and the first light signal and the second light signal Light signals are emitted alternately. The method for controlling an optical mouse as described in Claim 55, wherein the first reference value of illumination refers to the sum or average value of the illumination of all or some pixels of the first reflected image, and the second reference value of illumination Refers to the sum or average of the illuminance of all or some pixels of the second reflection image. The method for controlling an optical mouse as described in Claim 9, wherein the comparison result is the difference or ratio between the first illuminance reference value and the second illuminance reference value, if the comparison result is judged to be less than a threshold value, it is judged that the optical mouse is away from the work surface. An optical mouse, which includes: a housing; a light source, which is arranged in the housing and provides a light signal to the outside of the housing; A sensing unit, which is arranged in the casing, and receives a reflected light signal of the light signal; and a control unit, which is arranged in the casing, and the control unit controls the light source to provide the light signal, wherein The control unit controlling the light source to provide the light signal includes the following modes: when the optical mouse is operated on a work surface, control the transmission and reception of the light signal at a first frame rate; when the optical mouse leaves the work surface When the optical mouse controls the transmission and reception of optical signals at a second frame rate, wherein the second frame rate is greater than the first frame rate; when the optical mouse controls the transmission and reception of optical signals at the second frame rate, it is judged Whether the optical mouse returns to the work surface, if so, the optical mouse will switch back to the first frame rate to control the emission and reception of the light signal after a certain time delay. The transmission and reception of optical signals are controlled at the second frame rate. The optical mouse as described in claim 11, wherein when the optical mouse is operated on the work surface, the control unit further judges whether the optical mouse has a displacement, and if so, controls the optical signal at the first frame rate if not, then control the transmission and reception of optical signals at a third frame rate; wherein the third frame rate is less than the first frame rate. The optical mouse as claimed in claim 11, wherein the first frame rate is selected from a first range, and the second frame rate is selected from a second range. The optical mouse according to claim 12, wherein the first frame rate is selected from a first range, the second frame rate is selected from a second range, and the third frame rate is selected from a third range. The optical mouse as described in claim item 11, wherein when the control unit controls the light source to provide the light signal, at least one light-emitting period is included, and when the control unit judges whether the optical mouse leaves the work surface, the following steps are included: In each of the light-emitting periods, a first light signal is emitted to obtain a first reflected image, and a second light signal is emitted to obtain a second reflected image, and the magnitude of the first light signal is the same as that of the second light signal. The magnitudes of the two light signals are different; calculating a first illuminance reference value of the first reflected image and a second illuminance reference value of the second reflected image and obtaining a comparison result; and according to the comparison result It is judged whether the optical mouse is away from the work surface. The optical mouse according to claim 15, wherein the first illuminance reference value and the second illuminance reference value are respectively obtained in different lighting cycles. The optical mouse as claimed in claim 15 or 16, wherein the second reflection image and the first reflection image are adjacent in time sequence. The optical mouse as described in claim 15, wherein in each light-emitting cycle, the first light signal and the second light signal are respectively emitted multiple times, and the first light signal and the second light signal are Alternate firing. The optical mouse as described in claim 15, wherein the first illuminance reference value refers to the sum or average of the illuminance of all or some pixels of the first reflection image, and the second illuminance reference value refers to the The sum or average of the illuminance of all or some pixels of the second reflection image. The optical mouse as described in claim 19, wherein the comparison result is the difference or ratio between the first illuminance reference value and the second illuminance reference value, if it is judged that the comparison result is less than a threshold value, then It is determined that the optical mouse is off the work surface.

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