Electronic device, electronic device control method and program

Abstract

To provide an electronic apparatus optimally executing determination relating to a wearing state, control method of the electronic apparatus and a program.SOLUTION: An electronic apparatus to be worn by a user comprises a light emitting section for emitting light to a user's skin, a light receiving section provided at a location capable of receiving light reflected by the user's skin when the electronic apparatus is worn on the user and the light emitting section emits the light, and a control section. The control section executes skin determination for determining whether or not the user's skin satisfies a prescribed darkness condition based on an amount of received light by the light receiving section, executes wearing determination for determining whether or not the electronic apparatus is mounted on the user based on at least the amount of received light by the light receiving section, and when determining that it satisfies the darkness condition in the skin determination, does not execute the wearing determination.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to an electronic device, a control method for an electronic device, and a program. [Background technology]

[0002] Conventionally, in electronic devices worn by a user, a technology is known in which light reflected from the user's skin is received by a light receiving unit, and pulse is detected based on the change in the amount of received light (for example, Patent Document 1). In addition, a technology is known in which, by utilizing the fact that the amount of light received by the light receiving unit decreases when the electronic device is not worn by the user, it is determined whether the electronic device is worn by the user based on the amount of received light. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4476664 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the electronic device is worn by a user, the amount of light reflected by the user's skin and incident on the light receiving unit (i.e., the amount of light received by the light receiving unit) becomes smaller as the skin becomes darker. Therefore, depending on the darkness of the user's skin, even if the electronic device is worn by the user, there is a problem that the electronic device may be erroneously determined to be not worn due to the small amount of light received.

[0005] An object of the present invention is to provide an electronic device, a control method for an electronic device, and a program for appropriately determining the wearing state. [Means for solving the problem]

[0006] In order to solve the above problems, the electronic device of the present invention comprises: Wearable by the user , detect pulse An electronic device, A light emitting unit that emits light onto the skin of the user; a light receiving unit provided at a position capable of receiving the light reflected by the skin of the user when the device is worn by the user and when the light emitting unit emits the light; A control unit; Equipped with The control unit is The user's skin, Based on the amount of light received by the light receiving unit To determine the lightness or darkness of the user's skin performing a skin determination to determine whether or not a predetermined darkness condition is satisfied; When it is determined that the darkness condition is not satisfied in the skin determination, A wearing determination is performed to determine whether or not the device is worn by a user based on at least the amount of light received by the light receiving unit. repetition Go, When it is determined that the darkness condition is satisfied in the skin determination, the wearing determination is not performed. It is characterized by:

[0007] In order to solve the above problems, a method for controlling an electronic device according to the present invention includes: A method for controlling an electronic device worn by a user, the electronic device comprising: a light-emitting unit that emits light to the skin of the user; and a light-receiving unit that is provided at a position capable of receiving the light reflected by the skin of the user when the electronic device is worn by the user and when the light-emitting unit is emitting the light, the method comprising the steps of: a skin determination step of determining whether or not the user's skin satisfies a predetermined darkness condition based on the amount of light received by the light receiving unit; a wearing determination step of determining whether or not the device is worn by a user based on at least the amount of light received by the light receiving unit; Including, When it is determined in the skin determination step that the darkness condition is satisfied, the wearing determination step is not performed. It is characterized by:

[0008] In order to solve the above problems, the program of the present invention comprises: A program executed by a computer provided in an electronic device worn by a user, the electronic device including: a light-emitting unit that emits light to the skin of a user; and a light-receiving unit that is provided at a position capable of receiving the light reflected by the skin of the user when the electronic device is worn by the user and when the light-emitting unit is emitting the light, causing the computer to function as a control means; The control means performing a skin determination to determine whether or not the user's skin satisfies a predetermined darkness condition based on the amount of light received by the light receiving unit; performing a wearing determination for determining whether or not the device is worn by a user based on at least the amount of light received by the light receiving unit; When it is determined that the darkness condition is satisfied in the skin determination, the wearing determination is not performed. It is characterized by: Effect of the Invention

[0009] According to the present invention, it is possible to suitably perform a determination regarding the wearing state. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view showing the appearance of an electronic timepiece. [Diagram 2] FIG. [Diagram 3] FIG. 2 is a block diagram showing the functional configuration of the electronic timepiece. [Figure 4] 11A and 11B are diagrams illustrating an example of differences in the amount of received light depending on the darkness of the skin. [Diagram 5] 10 is a flowchart showing a control procedure of a pulse rate measurement process. [Figure 6] 10 is a flowchart showing a control procedure of pulse rate measurement start processing; [Figure 7] 10 is a flowchart showing a control procedure of skin determination processing. [Figure 8] 10 is a flowchart showing a control procedure of an attachment determination process. [Figure 9]13 is a flowchart showing a control procedure of a pulse rate measurement restart process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an electronic device, a control method for an electronic device, and a program according to the present invention will be described with reference to the drawings.

[0012] (Structure of an Electronic Clock) FIG. 1 is a perspective view showing the external appearance of an electronic timepiece 1. As shown in FIG. The electronic watch 1 (electronic device) is a wristwatch that is worn on the user's wrist. The electronic watch 1 comprises a main body 2 provided with a display screen 121 and operation buttons 131, etc., and a belt 3 attached to the main body 2. The display screen 121 displays digital information in a dot matrix format. On the display screen 121, the electronic watch 1 displays basic information such as the time and date, as well as measurement results of the user's pulse rate (heart rate), etc.

[0013] FIG. 2 is a side view of the electronic timepiece 1. The electronic watch 1 includes a light-emitting unit 15 and a light-receiving unit 17 inside the main body 2, which are used to detect the pulse. The light-emitting unit 15 and the light-receiving unit 17 are provided on the back surface of the main body 2, i.e., near the surface that touches the user's wrist when worn. The light-emitting unit 15 emits light from the back surface of the main body 2 toward the outside. When the electronic watch 1 is worn by the user, the light emitted from the light-emitting unit 15 is reflected by the skin of the user's wrist. The light-receiving unit 17 is provided in a position where it can receive the light reflected by the user's skin. A part of the light irradiated to the user's skin is absorbed by the blood in the blood vessels. Therefore, the amount of light reflected from the skin and received by the light-receiving unit 17 changes over time according to the change in blood flow rate accompanying the pulsation of the heart. The pulse is detected based on this change in the amount of received light, and the pulse rate is measured based on the detected pulse.

[0014] FIG. 3 is a block diagram showing the functional configuration of the electronic watch 1. As shown in FIG. The electronic watch 1 includes a CPU 10 (Central Processing Unit), a memory 11 (storage unit), a display unit 12, an operation reception unit 13, an oscillator circuit 141, a frequency division circuit 142, a timing circuit 143, a light emitting unit 15, a light emitting driving unit 16, a light receiving unit 17, an acceleration sensor 18, and an A / D converter 19.

[0015] The CPU 10 is a processor that performs various arithmetic processing and controls the operation of each part of the electronic watch 1. The CPU 10 reads and executes a program 111 stored in the memory 11, thereby functioning as a control unit (control means) that performs various control operations.

[0016] For example, the CPU 10 causes the display unit 12 to display the date and time being counted by the timer circuit 143. The CPU 10 also detects the pulse based on changes in the amount of light received by the light receiving unit 17, and causes the display unit 12 to display the measurement result of the pulse rate (number of pulses per minute). The CPU 10 also performs a skin judgment to determine whether or not the user's skin meets a predetermined darkness condition based on the amount of light received by the light receiving unit 17. The CPU 10 also performs a wearing judgment to determine whether or not the electronic watch 1 (the device itself) is worn by the user based on the amount of light received by the light receiving unit 17 and the detection result of the acceleration by the acceleration sensor 18. The skin judgment and wearing judgment will be described in detail later.

[0017] The memory 11 provides a working memory space for the CPU 10 and stores various data. The memory 11 includes, for example, a RAM (Random Access Memory) and a non-volatile memory. The RAM is used for the calculation processing of the CPU 10 and also stores temporary data. The non-volatile memory is, for example, a flash memory, and stores various data in addition to the program 111. The program 111 includes a control program for controlling the basic operation of the electronic watch 1, as well as an application program for measuring the pulse rate and displaying the result on the display unit 12 (hereinafter, referred to as a "pulse rate measurement application"). The data stored in the memory 11 includes a wearing determination execution flag 112. The wearing determination execution flag 112 is used to determine whether or not to execute a wearing determination process described later. The wearing determination execution flag 112 is, for example, 1-bit data.

[0018] The display unit 12 includes a display screen 121, and performs digital display on the display screen 121 under the control of the CPU 10. Here, the display screen 121 is capable of performing display in a dot matrix format, and is, for example, a liquid crystal display screen.

[0019] The operation acceptance unit 13 has a plurality of operation buttons 131. The operation acceptance unit 13 accepts an input operation (e.g., a pressing operation) by the user on the operation buttons 131 and outputs the operation as an input signal to the CPU 10. The CPU 10 executes a process corresponding to the function of the operation button 131 for which the input operation has been performed. The functions assigned to each operation button 131 may be switched depending on the operation mode of the electronic watch 1. The operation buttons 131 may include a crown. The operation acceptance unit 13 may also have a touch panel provided over the display screen 121.

[0020] The oscillator circuit 141 generates a clock signal of a predetermined oscillation frequency and outputs it to the frequency divider circuit 142. The frequency divider circuit 142 divides the clock signal input from the oscillator circuit 141, converts it to a frequency required for the operation of each part of the electronic clock 1, and outputs it. The destinations for the signal divided by the frequency divider circuit 142 include a clock circuit 143.

[0021] The clock circuit 143 counts the signal of a predetermined frequency input from the frequency divider circuit 142 to count and hold the current date and time. The format of the date and time held by the clock circuit 143 is not limited to that expressed by year, month, day, hour, minute, and second, and may be any appropriate format suitable for processing by the CPU 10 or the like.

[0022] The light-emitting unit 15 includes a light-emitting element that emits light, such as an LED (Light Emitting Diode). The light-emitting unit 15 of this embodiment includes an LED that emits green light that is easily absorbed by hemoglobin in blood, for example, light with a peak wavelength of 520 nm to 530 nm. The LED of the light-emitting unit 15 emits light in response to a drive current supplied from the light-emitting drive unit 16.

[0023] The light emission drive unit 16 controls the output of a drive current to the light emission unit 15 in accordance with a control signal from the CPU 10, thereby causing the LED of the light emission unit 15 to emit light or to turn off.

[0024] The light receiving unit 17 includes a light receiving element that detects light and outputs an electrical signal according to the amount of light received. Here, the amount of light received is, for example, the intensity of the incident light. For example, a photodiode or an illuminance sensor can be used as the light receiving element.

[0025] The acceleration sensor 18 detects the acceleration of the electronic timepiece 1 caused by the user's actions, etc., and outputs an electrical signal corresponding to the acceleration. The acceleration sensor 18 detects, for example, the acceleration in each of the three axial directions of a Cartesian coordinate system.

[0026] The A / D converter 19 converts the electrical signals output from the light receiving unit 17 and the acceleration sensor 18 into digital data and outputs it to the CPU 10. Thus, digital data representing the amount of light received by the light receiving unit 17 is output from the A / D converter 19 to the CPU 10. In addition, digital data representing the acceleration detection result by the acceleration sensor 18 is output from the A / D converter 19 to the CPU 10. A separate A / D converter 19 may be provided for each of the light receiving unit 17 and the acceleration sensor 18.

[0027] (Electronic clock operation) Next, the operation of the electronic timepiece 1 will be described, focusing on the operation relating to measuring the pulse rate.

[0028] As described above, measuring the pulse rate in the electronic watch 1 (and therefore detecting the pulse rate) involves illuminating the LED of the light-emitting unit 15 (hereinafter simply referred to as illuminating the light-emitting unit 15). For this reason, if the electronic watch 1 is removed from the user's wrist while measuring the pulse rate, it is preferable, from the standpoint of appearance and power consumption, to turn off the light-emitting unit 15 and stop measuring the pulse rate.

[0029] For this reason, in the electronic watch 1 of this embodiment, after the measurement of the pulse rate is started, a wearing judgment is performed to judge whether or not the device is worn by the user. This wearing judgment is performed based on whether or not the amount of light received from the light receiving unit 17 is greater than a predetermined reference value (second reference value V2 shown in FIG. 4). When the electronic watch 1 is worn on the user's wrist, the light emitted from the light emitting unit 15 is reflected by the skin and enters the light receiving unit 17. On the other hand, when the electronic watch 1 is removed from the user's wrist, the light emitted from the light emitting unit 15 is diffused without being reflected by the skin, and almost no light returns to the light receiving unit 17. Therefore, when the electronic watch 1 is not worn by the user, the amount of light received by the light receiving unit 17 is greatly reduced compared to when the electronic watch 1 is worn. For this reason, it is possible to judge whether or not the electronic watch 1 is worn by the user based on whether or not the amount of light received by the light receiving unit 17 is greater than the second reference value V2. The second reference value V2 is set to a value between the amount of light received when the electronic watch 1 is worn by the user and the amount of light received when the electronic watch 1 is not worn by the user. If it is determined that the electronic timepiece 1 is not being worn by the user, measurement of the pulse rate is stopped.

[0030] However, the proportion of light emitted from the light-emitting unit 15 that is reflected by the user's skin and enters the light-receiving unit 17 decreases as the skin becomes darker (for example, the darker the skin color). Thus, the amount of light received by the light-receiving unit 17 varies greatly depending on the darkness of the skin of the user wearing the electronic watch 1. For this reason, depending on the darkness of the skin, even if the electronic watch 1 is worn by the user, the amount of light received may be small and it may be erroneously determined that the user is not wearing the electronic watch 1. If such an erroneous determination occurs, the measurement of the pulse rate will stop at an unintended timing while the electronic watch 1 is being worn. Here, the darkness of the skin includes darkness caused by the color of the natural skin, as well as darkness caused by changes in the reflectance and diffusion state of light due to cosmetics applied to the skin, etc.

[0031] FIG. 4 is a diagram showing an example of the difference in the amount of received light depending on the darkness of the skin. Fig. 4(a) shows an example of the amount of light received by the light receiving unit 17 when the electronic watch 1 is used by a user with light skin. Fig. 4(b) shows an example of the amount of light received by the light receiving unit 17 when the electronic watch 1 is used by a user with dark skin. In more detail, Fig. 4(a) shows the case where the electronic watch 1 is used by a user with skin classified as Type I in the Fitzpatrick skin type. Meanwhile, Fig. 4(b) shows the case where the electronic watch 1 is used by a user with skin classified as Type VI in the Fitzpatrick skin type.

[0032] 4(a) and 4(b), the electronic timepiece 1 is worn by the user from time t0 to time t1. At time t1, the electronic timepiece 1 is removed from the user's wrist, and at time t2, the electronic timepiece 1 is placed on a table.

[0033] In this situation, as shown in Figure 4(a), in the case of light skin, the amount of received light is greater than the second reference value V2 when the electronic watch 1 is worn (timings t0 to t1), so it is appropriately determined that the electronic watch 1 is being worn. Also, when the electronic watch 1 is taken off and left to rest (from timing t2 onwards), the amount of received light is equal to or less than the second reference value V2, so it is appropriately determined that the electronic watch 1 is not being worn.

[0034] On the other hand, as shown in Figure 4(b), in the case of dark skin, the amount of received light is below the second reference value V2 even when worn (timing t0 to t1), so even if the electronic watch 1 is worn by the user, an inappropriate determination is made that the electronic watch is not being worn.

[0035] Therefore, in the electronic watch 1 of this embodiment, a skin judgment is performed to judge whether or not the user's skin meets a predetermined darkness condition based on the amount of light received by the light receiving unit 17 when worn. Then, if it is determined that the darkness condition is not met (i.e., if it is determined that the skin is light), a wearing judgment is performed. On the other hand, if it is determined that the darkness condition is met (i.e., if it is determined that the skin is dark), a wearing judgment is not performed. This prevents the occurrence of a malfunction in which the watch is erroneously judged to be not worn despite being worn due to dark skin. The user's skin that is the subject of the skin judgment may be bare skin, or skin with cosmetics or the like applied.

[0036] In the skin judgment, if the amount of light received by the light receiving unit 17 is equal to or less than the first reference value V1, it is judged that the darkness condition is met. Here, as shown in FIG. 4(a) and FIG. 4(b), it is preferable that the first reference value V1 is greater than the second reference value V2. The amount of light received by the light receiving unit 17 when worn may vary depending on the manner in which the electronic watch 1 is worn and the brightness of the environment, even for the same user. Therefore, when the skin judgment is performed using the second reference value V2, even if it is judged that the darkness condition is not met (i.e., the skin is light), the amount of light received when the wearing judgment is performed may be equal to or less than the second reference value V2, resulting in an erroneous judgment that the watch is not worn. By performing the skin judgment using the first reference value V1 obtained by adding a predetermined margin to the second reference value V2, it is possible to reduce such erroneous judgments.

[0037] The method of skin determination can also be expressed as follows. That is, in the skin determination, it is determined whether or not the user's skin satisfies a predetermined brightness condition based on the amount of light received by the light receiving unit 17 when the device is worn. Then, if it is determined that the brightness condition is satisfied (i.e., if it is determined that the skin is light), a wearing determination is made. On the other hand, if it is determined that the brightness condition is not satisfied (i.e., if it is determined that the skin is dark), a wearing determination is not made. In this case, in the skin determination, it is determined that the brightness condition is satisfied when the amount of light received by the light receiving unit 17 is greater than the first reference value V1.

[0038] As shown in FIG. 4(b), even if the darkness condition is met and the amount of received light is smaller than the second reference value V2 when the device is worn, the fluctuation in the amount of received light corresponding to the change in blood flow can be detected, so that it is possible to detect the pulse and measure the pulse rate.

[0039] Next, a pulse rate measurement process for causing the electronic timepiece 1 to perform the pulse rate measurement operation, including the skin determination and the wearing determination, described above, will be described. FIG. 5 is a flowchart showing a control procedure of the pulse rate measurement process by the CPU 10. When the pulse rate measurement process is started, the CPU 10 executes a pulse rate measurement start process (step S101).

[0040] FIG. 6 is a flowchart showing a control procedure by the CPU 10 for starting pulse rate measurement. When the pulse rate measurement start process is started, the CPU 10 judges whether or not there is a request to start pulse rate measurement (step S201). For example, when a user's input operation for starting pulse rate measurement is accepted on the pulse rate measurement application, it is judged that there is a request to start pulse rate measurement. When it is judged that there is no request to start pulse rate measurement ("NO" in step S201), the CPU 10 executes the process of step S201 again.

[0041] When it is determined that there is a request to start measuring the pulse rate ("YES" in step S201), the CPU 10 acquires the detection result of the acceleration by the acceleration sensor 18 (step S202).

[0042] The CPU 10 judges whether the change in acceleration in the acquired acceleration detection result is equal to or greater than a predetermined judgment criterion (step S203). If the change in acceleration is equal to or greater than the judgment criterion, it is deemed that the user is wearing the electronic watch 1, and the process related to pulse rate measurement proceeds from then on. The judgment criterion is set so that the acceleration when the electronic watch 1 is worn by the user is likely to be equal to or greater than the judgment criterion. In other words, the judgment criterion is set so that it is near the lower limit of the range of acceleration changes that occur in response to the user's movements when the electronic watch 1 is worn by the user. If it is judged that the change in acceleration is less than the judgment criterion ("NO" in step S203), it can be determined that the electronic watch 1 is not worn by the user and it is not appropriate to start pulse rate measurement, so the CPU 10 executes the process of step S203 again without proceeding to the next step.

[0043] If it is determined that the change in acceleration is equal to or greater than the judgment criterion ("YES" in step S203), CPU 10 starts measuring the pulse rate. That is, it turns on light-emitting unit 15 (step S204), periodically obtains the detection result of the amount of light received by light-receiving unit 17 (step S205), and detects the pulse rate from the change in the obtained amount of light received. The frequency of obtaining the amount of light received by light-receiving unit 17 is not particularly limited, but can be, for example, every 10 msec. CPU 10 calculates the pulse rate based on the detection result of the pulse rate, and outputs the obtained pulse rate (displays it on display unit 12) (step S206). When step S206 ends, the CPU 10 ends the pulse rate measurement start process, and returns the process to the pulse rate measurement process of FIG.

[0044] In FIG. 5, when the pulse rate measurement start process (step S101) ends, the CPU 10 executes a skin determination process (step S102: skin determination step).

[0045] FIG. 7 is a flowchart showing a control procedure of the skin determination process by the CPU 10. When the skin determination process is started, the CPU 10 determines whether or not the amount of light received by the light receiving unit 17 is equal to or less than the first reference value V1 (step S301). Here, the determination may be made using any one of the data of the amount of light received by the light receiving unit 17 acquired for detecting the pulse rate.

[0046] If it is determined that the amount of received light is equal to or less than the first reference value V1 ("YES" in step S301), the CPU 10 determines that the skin satisfies the darkness condition (step S302), and sets the value of the wearing determination execution flag to "0" (step S303).

[0047] If it is determined that the amount of received light is greater than the first reference value V1 ("NO" in step S301), the CPU 10 determines that the skin does not satisfy the darkness condition (step S304), and sets the value of the wearing determination execution flag to "1" (step S305).

[0048] This skin assessment process is performed when it is determined in the pulse rate measurement start process of Fig. 6 that the change in acceleration is equal to or greater than the assessment criterion ("YES" in step S203) and pulse rate measurement (step S206) has started. That is, skin assessment is performed based on the amount of light received by the light receiving unit 17 when the pulse is being detected. This allows appropriate skin assessment to be performed based on the amount of light received that reflects the brightness of the skin while the electronic watch 1 is worn by the user. When step S303 or S304 ends, the CPU 10 ends the skin determination process, and returns the process to the pulse rate measurement process of FIG.

[0049] 5, when the skin determination process (step S102) is completed, the CPU 10 determines whether the wearing determination execution flag is "1" (step S103). If it is determined that the wearing determination execution flag is "1" ("YES" in step S103), the CPU 10 executes the wearing determination process (step S104: wearing determination step).

[0050] FIG. 8 is a flowchart showing a control procedure of the mounting determination process by the CPU 10. When the wearing determination process is started, the CPU 10 assigns "0" to a variable N that indicates the number of non-wearing detections (step S401).

[0051] The CPU 10 acquires the detection result of the amount of received light by the light receiving unit 17 and the detection result of the acceleration by the acceleration sensor 18 (step S402). Furthermore, the CPU 10 judges whether or not the change in acceleration in the acquired detection result of the acceleration is equal to or greater than the above-mentioned judgment criterion (step S403).

[0052] If it is determined that the change in acceleration is less than the criterion ("NO" in step S403), the CPU 10 determines whether the amount of light received by the light receiving unit 17 is greater than a second reference value V2 (step S404). If it is determined that the amount of light received is equal to or less than the second reference value V2 ("NO" in step S404), the change in acceleration is less than the criterion and the amount of light received is equal to or less than the second reference value V2 for wearing determination, so there is a possibility that the electronic watch 1 is not being worn by the user. Therefore, the CPU 10 counts up the variable N, which indicates the number of times non-wearing has been detected (step S405).

[0053] The CPU 10 judges whether the variable N is equal to or greater than the reference number of times (step S406). If it is judged that the variable N is equal to or greater than the reference number of times ("NO" in step S406), the CPU 10 returns the process to step S402 and executes the processing loop of steps S402 to S406 again. If it is judged that the variable N is equal to or greater than the reference number of times ("YES" in step S406), the CPU 10 judges that the electronic watch 1 is not worn by the user (step S407). In this way, when the processing loop of steps S402 to S406 is repeated until the variable N becomes equal to the reference number of times, in other words, when it is continuously judged in the processing loop that there is a possibility of non-wearing for a predetermined time, the process proceeds to step S407 and it is judged that the electronic watch 1 is not worn. The reference number of times is determined so that the time required for the variable N to become the reference number of times is the above-mentioned predetermined time. The predetermined time can be set arbitrarily, for example, about 5 seconds.

[0054] On the other hand, if it is determined in step S403 that the change in acceleration is greater than or equal to the judgment criterion ("YES" in step S403), or if it is determined in step S404 that the amount of received light is greater than the second reference value V2 ("YES" in step S404), the CPU 10 determines that the electronic watch 1 is being worn by the user (step S408). With this judgment method, even if the user wearing the electronic watch 1 keeps their arm still, for example, it can be appropriately determined that the electronic watch 1 is being worn by the user based on the amount of light received by the light receiving unit 17 being greater than or equal to the second reference value V2. This allows for more accurate wearing judgment than a judgment method that uses only the detection results from the acceleration sensor 18. When step S407 or step S408 ends, the CPU 10 ends the wearing determination process, and returns the process to the pulse rate measurement process of FIG.

[0055] 5, when the wearing determination process (step S104) is completed, the CPU 10 switches the subsequent process depending on the result of the wearing determination (step S105). If the determination result is "not wearing", the CPU 10 turns off the light emitting unit 15 and stops pulse detection and pulse rate measurement (step S106). After that, the CPU 10 executes pulse rate measurement restart process to restart pulse rate measurement at an appropriate timing when the electronic watch 1 is re-worn.

[0056] FIG. 9 is a flowchart showing a control procedure by the CPU 10 for the pulse rate measurement restart process. When the pulse rate measurement restart process is started, CPU 10 acquires the acceleration detection result by acceleration sensor 18 (step S501). CPU 10 judges whether the change in acceleration in the acquired acceleration detection result is equal to or greater than the above-mentioned criterion (step S502), and if it is judged that the change in acceleration is less than the criterion ("NO" in step S502), the process returns to step S501.

[0057] If it is determined that the change in acceleration is equal to or greater than the criterion ("YES" in step S502), CPU 10 turns on light-emitting unit 15 (step S503) and periodically acquires the detection result of the amount of light received by light-receiving unit 17 (step S504). The frequency of acquiring the amount of light received here may be lower than the detection frequency when detecting the pulse, and may be, for example, about several tens of msec.

[0058] The CPU 10 judges whether the amount of light received by the light receiving unit 17 is greater than the second reference value V2 (step S505). If it is judged that the amount of light received is equal to or less than the second reference value V2 ("NO" in step S505), the CPU 10 again obtains the acceleration detection result by the acceleration sensor 18 and judges whether the change in acceleration is equal to or greater than the judgment reference (step S506). If it is judged that the change in acceleration is less than the reference value ("NO" in step S506), it can be determined that the electronic watch 1 is not worn by the user at this stage and it is not appropriate to resume pulse rate measurement. Therefore, the CPU 10 turns off the light emitting unit 15 (step S507) and returns the process to step S501.

[0059] On the other hand, if it is determined in step S506 that the change in acceleration is greater than or equal to the criterion ("YES" in step S506), the CPU 10 returns the process to step S504 and executes the process loop of steps S504 to S506 again. If it is determined in step S505 within this process loop that the amount of received light is greater than the second reference value V2 ("YES" in step S505), it can be determined that the electronic watch 1 may be worn by the user. For this reason, the CPU 10 further confirms that the electronic watch 1 is being worn by the user, and then executes the processes of steps S508 to S511 to resume pulse rate measurement.

[0060] First, the CPU 10 judges whether the amount of light received by the light receiving unit 17 is greater than the second reference value V2 and satisfies a predetermined stability condition (step S508). Here, the stability condition is judged, for example, by the following method. That is, when the smaller of the two amounts of light received acquired at the two most recent acquisition timings is R1 and the larger is R2, it is judged that the stability condition is satisfied if (R2-R1) / R1 falls below a predetermined upper limit. The upper limit can be set as appropriate, but the smaller the upper limit, the less likely it is that the measurement of the pulse rate will be resumed in a non-wearing state. The method of judging the stability condition is not limited to the above.

[0061] If it is determined that the amount of received light is greater than the second reference value V2 and satisfies the stability condition ("YES" in step S508), the CPU 10 starts periodically acquiring the amount of received light for measuring the pulse rate (step S509). Here, the amount of received light may be acquired more frequently (for example, every 10 msec) than in step S504. The CPU 10 starts detecting the pulse based on the acquired amount of received light.

[0062] The CPU 10 again determines whether the amount of light received by the light receiving unit 17 is greater than the second reference value V2 and satisfies the predetermined stability condition (step S510). If it is determined in step S508 or step S509 that the amount of light received is equal to or less than the second reference value V2 or does not satisfy the stability condition (step S508, S510: NO), the CPU 10 returns to processing step S504.

[0063] In step S510, if it is determined that the amount of received light is greater than the second reference value V2 and satisfies the stability condition ("YES" in step S510), the CPU 10 measures the pulse rate based on the frequency of pulse detection, etc., and outputs the obtained pulse rate for display on the display unit 12 (step S511). In other words, the measurement of the pulse rate is resumed. The reason why a determination similar to that in step S508 is made again in step S510 is to resume the measurement of the pulse rate after confirming that the user has not removed the electronic watch 1 between steps S508 and S510. When step S511 ends, the CPU 10 ends the pulse rate measurement restart process, and returns the process to the pulse rate measurement process of FIG.

[0064] When the pulse rate measurement restart process (step S107) in FIG. 5 ends, the CPU 10 returns the process to step S103.

[0065] In step S103, when it is determined that the wearing determination execution flag is "0" ("NO" in step S103), CPU 10 does not execute the processes of steps S104 to S107, and shifts the process to step S108. Also, in step S105, when it is determined that the determination result of the wearing determination process is "wearing", CPU 10 shifts the process to step S108.

[0066] In step S108, the CPU 10 judges whether or not an instruction to end the pulse rate measurement has been given. For example, when a user's input operation to end the pulse rate measurement is accepted on the pulse rate measurement application, it is judged that an instruction to end the pulse rate measurement has been given. If it is judged that the instruction to end has not been given ("NO" in step S108), the CPU 10 returns the process to step S103. If it is judged that an instruction to end has been given ("YES" in step S108), the CPU 10 turns off the light-emitting unit 15 to stop the detection of the pulse and the measurement of the pulse rate (step S109), and ends the pulse rate measurement process.

[0067] (effect) As described above, the electronic watch 1 according to this embodiment as an electronic device worn by a user includes the light-emitting unit 15 that emits light to the skin of the user, the light-receiving unit 17 that is provided at a position that can receive light reflected by the skin of the user when the device is worn by the user and when the light-emitting unit 15 is emitting light, and the CPU 10 that functions as a control unit. The CPU 10 as a control unit performs a skin determination to determine whether the user's skin satisfies a predetermined darkness condition based on the amount of light received by the light-receiving unit 17. The CPU 10 as a control unit also performs a wearing determination to determine whether the device is worn by the user based on at least the amount of light received by the light-receiving unit 17, and does not perform a wearing determination when it is determined that the darkness condition is satisfied in the skin determination. This allows the determination regarding the wearing state to be performed favorably. For example, it is possible to make it difficult to cause a problem in which the electronic watch 1 is erroneously determined to be not worn when worn by the user.

[0068] In addition, the CPU 10 as the control unit performs a wearing determination when it is determined that the darkness condition is not satisfied in the skin determination. According to this, since the wearing determination is performed when the skin is light, it is possible to prevent a problem in which a false determination that the device is not being worn due to a small amount of light reflected by the skin being made.

[0069] Furthermore, the CPU 10 as the control unit detects the pulse based on changes in the amount of light received by the light receiving unit 17. In such a configuration, skin determination can be performed using the light emitting unit 15 and the light receiving unit 17 for detecting the pulse. This makes it possible to perform skin determination with less likelihood of erroneous determination, while avoiding an increase in the complexity of the configuration of the electronic watch 1 and an increase in manufacturing costs.

[0070] Furthermore, the CPU 10 as the control unit performs skin assessment based on the amount of light received by the light receiving unit 17 when detecting the pulse. This allows appropriate skin assessment to be performed based on the amount of light received that reflects the brightness of the skin while the electronic watch 1 is worn by the user.

[0071] Furthermore, the CPU 10 as the control unit determines that the darkness condition is satisfied in the skin determination when the amount of light received by the light receiving unit 17 is equal to or less than the first reference value V1. This allows the skin determination to be performed by simple processing.

[0072] Furthermore, when the amount of light received by the light receiving unit 17 is greater than the second reference value V2 in the wearing determination, the CPU 10 as the control unit determines that the device is being worn by the user, and the first reference value V1 is greater than the second reference value V2. In this way, by performing the skin determination using the first reference value V1 greater than the second reference value V2 used in the wearing determination, even if the amount of light received in the wearing determination becomes lower than the first reference value V1 due to the manner of wearing or the brightness of the environment, it is possible to prevent an erroneous determination that the device is not being worn immediately.

[0073] The electronic watch 1 also includes an acceleration sensor 18 that detects the acceleration of the device itself, and the CPU 10 as the control unit performs a skin assessment when the change in acceleration detected by the acceleration sensor 18 is equal to or greater than a predetermined assessment criterion. This allows appropriate skin assessment to be performed based on the amount of received light that reflects the brightness of the skin while the electronic watch 1 is worn by the user.

[0074] Furthermore, the control method of the electronic watch 1 as an electronic device according to this embodiment includes a skin determination step of determining whether or not the user's skin satisfies a predetermined darkness condition based on the amount of light received by the light receiving unit 17, and a wearing determination step of determining whether or not the device is worn by the user based on at least the amount of light received by the light receiving unit 17, and if it is determined in the skin determination step that the darkness condition is satisfied, the wearing determination step is not performed. This allows for an optimal determination of the wearing state. For example, it is possible to prevent a problem in which the electronic watch 1 is erroneously determined to be not worn when it is worn by the user.

[0075] Moreover, the program 111 according to this embodiment causes the CPU 10, which is a computer provided in the electronic watch 1 as an electronic device, to function as a control means. The control means performs a skin judgment to judge whether or not the user's skin satisfies a predetermined darkness condition based on the amount of light received by the light receiving unit 17. The control means also performs a wearing judgment to judge whether or not the device is worn by the user based on at least the amount of light received by the light receiving unit 17, and does not perform a wearing judgment if it is judged that the darkness condition is satisfied in the skin judgment. By operating the electronic watch 1 with such a program 111, it is possible to preferably perform a judgment regarding the wearing state. For example, it is possible to make it difficult for a malfunction to occur in which the electronic watch 1 is erroneously judged to be not worn when it is worn by the user.

[0076] (others) The description of the above embodiment is merely an example of the electronic device, the control method for the electronic device, and the program according to the present invention, and the present invention is not limited to this. For example, the electronic device is not limited to the electronic watch 1. For example, the electronic device may be various wearable devices such as an activity meter. The electronic device may be any device that has a light emitting unit and a light receiving unit used for skin determination and wearing determination, and is not limited to devices capable of pulse detection. For an electronic device that does not detect pulse, for example, when the change in acceleration is equal to or greater than the above-mentioned determination condition, it may be assumed that the device is worn by a user and skin determination may be performed. The position where the electronic device is worn is not limited to the wrist.

[0077] Further, although the electronic watch 1 has been exemplified as one that displays digitally in a dot matrix format, this is not limited to this, and an analog type electronic watch that displays at least some of the information such as the time and pulse rate using hands may also be used.

[0078] Although the above description has been given with an example in which the pulse detection result is used to measure the pulse rate, the present invention is not limited to this example. The pulse detection result may be used, for example, to display a heartbeat pulse or to cause a blinking display in accordance with the pulse.

[0079] Also, an example has been described in which the skin determination process is performed and the wearing determination execution flag 112 is rewritten each time a pulse rate measurement process is performed, but this is not limited to the above. In cases where the user using the electronic watch 1 can be identified or where use by multiple users is not expected, the result of the skin determination in the first pulse rate measurement process may be used for the second and subsequent pulse rate measurement processes. In this case, the content of the wearing determination execution flag 112 determined in the skin determination process in the first pulse rate measurement process is stored in the setting data of the memory 11 in association with the user, and in the second and subsequent pulse rate measurement processes, it is possible to determine whether or not to perform the wearing determination based on this setting data.

[0080] In the above description, an example has been disclosed in which the non-volatile memory of the memory 11 is used as a computer-readable medium for the program according to the present invention, but the present invention is not limited to this example. As other computer-readable media, information recording media such as HDD, SSD, flash memory, and CD-ROM can be applied. In addition, a carrier wave is also applied to the present invention as a medium for providing data of the program according to the present invention via a communication line.

[0081] Furthermore, the detailed configuration and operation of each component of the electronic watch 1 as the electronic device in the above embodiment can of course be modified as appropriate without departing from the spirit of the present invention.

[0082] Although the embodiments of the present invention have been described, the scope of the present invention is not limited to the above-described embodiments, but includes the scope of the invention described in the claims and its equivalents. The inventions described in the claims originally attached to this application are set forth below. The claim numbers in the appended claims are the same as those in the claims originally attached to this application. [Additional Notes] <Claim 1> An electronic device worn by a user, A light emitting unit that emits light onto the skin of the user; a light receiving unit provided at a position capable of receiving the light reflected by the skin of the user when the device is worn by the user and when the light emitting unit emits the light; A control unit; Equipped with The control unit is performing a skin determination to determine whether or not the user's skin satisfies a predetermined darkness condition based on the amount of light received by the light receiving unit; performing a wearing determination for determining whether or not the device is worn by a user based on at least the amount of light received by the light receiving unit; When it is determined that the darkness condition is satisfied in the skin determination, the wearing determination is not performed. 1. An electronic device comprising: <Claim 2> 2. The electronic device according to claim 1, wherein the control unit performs the wearing determination when it is determined that the darkness condition is not satisfied in the skin determination. <Claim 3> 3. The electronic device according to claim 1, wherein the control unit detects a pulse rate based on a change in an amount of light received by the light receiving unit. <Claim 4> 4. The electronic device according to claim 3, wherein the control unit performs the skin determination based on an amount of light received by the light receiving unit when the pulse is detected. <Claim 5> 5. The electronic device according to claim 1, wherein the control unit determines that the darkness condition is satisfied when the amount of light received by the light receiving unit is equal to or less than a first reference value in the skin judgment. <Claim 6> The control unit determines that the device is worn by a user when an amount of light received by the light receiving unit is greater than a second reference value in the wearing determination, The first reference value is greater than the second reference value. 6. The electronic device according to claim 5, <Claim 7> An acceleration sensor is provided to detect the acceleration of the device itself; The control unit performs the skin determination when a change in acceleration detected by the acceleration sensor is equal to or greater than a predetermined determination criterion. 7. The electronic device according to claim 1, wherein the first and second electrodes are arranged in a first direction. <Claim 8> A method for controlling an electronic device worn by a user, the electronic device comprising: a light-emitting unit that emits light to the skin of the user; and a light-receiving unit that is provided at a position capable of receiving the light reflected by the skin of the user when the electronic device is worn by the user and when the light-emitting unit is emitting the light, the method comprising the steps of: a skin determination step of determining whether or not the user's skin satisfies a predetermined darkness condition based on the amount of light received by the light receiving unit; a wearing determination step of determining whether or not the device is worn by a user based on at least the amount of light received by the light receiving unit; Including, When it is determined in the skin determination step that the darkness condition is satisfied, the wearing determination step is not performed. 23. A method for controlling an electronic device comprising: <Claim 9> A program executed by a computer provided in an electronic device worn by a user, the electronic device including: a light-emitting unit that emits light to the skin of a user; and a light-receiving unit that is provided at a position capable of receiving the light reflected by the skin of the user when the electronic device is worn by the user and when the light-emitting unit is emitting the light, causing the computer to function as a control means; The control means performing a skin determination to determine whether or not the user's skin satisfies a predetermined darkness condition based on the amount of light received by the light receiving unit; performing a wearing determination for determining whether or not the device is worn by a user based on at least the amount of light received by the light receiving unit; When it is determined that the darkness condition is satisfied in the skin determination, the wearing determination is not performed. A program characterized by: [Explanation of symbols]

[0083] 1. Electronic clock (electronic device) 2 Main unit 3 Belt 10 CPU (control unit, control means) 11. Memory 111 Program 112 Wearing check execution flag 12 Display section 121 Display screen 13 Operation reception section 131 Operation Button 141 Oscillator Circuit 142 Frequency divider circuit 143 Timing circuit 15 Light emitting part 16 Light emitting driver 17 Light receiving part 18 Acceleration Sensor 19 A / D Converter V1 First reference value V2 Second reference value

Claims

1. An electronic device that is worn by a user and detects a pulse, A light emitting unit that emits light onto the skin of the user; a light receiving unit provided at a position capable of receiving the light reflected by the skin of the user when the device is worn by the user and when the light emitting unit emits the light; A control unit; Equipped with The control unit is performing a skin determination to determine whether or not the user's skin satisfies a predetermined darkness condition for determining the light or darkness of the user's skin based on the amount of light received by the light receiving unit; When it is determined that the darkness condition is not satisfied in the skin determination, a wearing determination is repeatedly performed to determine whether or not the device is worn by a user based on at least the amount of light received by the light receiving unit; When it is determined that the darkness condition is satisfied in the skin determination, the wearing determination is not performed.

1. An electronic device comprising:

2. The electronic device according to claim 1 , wherein the control unit detects a pulse based on a change in an amount of light received by the light receiving unit.

3. The electronic device according to claim 2 , wherein the control unit performs the skin determination based on an amount of light received by the light receiving unit when the pulse is detected.

4. The electronic device according to any one of claims 1 to 3, characterized in that, in the skin judgment, the control unit judges that the darkness condition is satisfied when the amount of light received by the light receiving unit is equal to or less than a first reference value.

5. The control unit determines that the device is worn by a user when an amount of light received by the light receiving unit is greater than a second reference value in the wearing determination, The first reference value is greater than the second reference value.

5. The electronic device according to claim 4.

6. An acceleration sensor is provided to detect the acceleration of the device itself; The control unit performs the skin determination when a change in acceleration detected by the acceleration sensor is equal to or greater than a predetermined determination criterion.

6. The electronic device according to claim 1, wherein the first and second electrodes are electrically connected to the first and second electrodes.

7. A method for controlling an electronic device that is worn by a user and detects a pulse rate, the method comprising: a light-emitting unit that emits light to the skin of a user; and a light-receiving unit that is provided at a position capable of receiving the light reflected by the skin of the user when the electronic device is worn by the user and when the light-emitting unit is emitting the light, the method comprising the steps of: a skin determination step of determining whether or not the user's skin satisfies a predetermined darkness condition for determining the light or dark of the user's skin based on the amount of light received by the light receiving unit; a wearing determination step of repeatedly determining whether or not the device is worn by a user based on at least the amount of light received by the light receiving unit when it is determined in the skin determination step that the darkness condition is not satisfied; Including, When it is determined in the skin determination step that the darkness condition is satisfied, the wearing determination step is not performed.

23. A method for controlling an electronic device comprising:

8. A program executed by a computer provided in an electronic device that is worn by a user and detects a pulse rate, the electronic device comprising: a light-emitting unit that emits light to the skin of a user; and a light-receiving unit that is provided at a position capable of receiving the light reflected by the skin of the user when the electronic device is worn by the user and when the light-emitting unit is emitting the light, the program comprising: causing the computer to function as a control means; The control means performing a skin determination to determine whether or not the user's skin satisfies a predetermined darkness condition for determining the light or darkness of the user's skin based on the amount of light received by the light receiving unit; When it is determined that the darkness condition is not satisfied in the skin determination, a wearing determination is repeatedly performed to determine whether or not the device is worn by a user based on at least the amount of light received by the light receiving unit; When it is determined that the darkness condition is satisfied in the skin determination, the wearing determination is not performed. A program characterized by:

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