Control device for digital rearview mirror and digital rearview mirror

Abstract

To provide a control technology of a digital room mirror capable of suppressing detection of infrared rays irradiated by an infrared irradiation device in a cabin of a vehicle mounted with the infrared irradiation device.SOLUTION: The digital rearview mirror control device 22 includes the LED control signal acquisition unit 221 that acquires the LED control signal for controlling the light emission of the LED included in the infrared irradiation device disposed in the interior of the vehicle, the illuminance acquisition unit 222 that acquires the illuminance information, and the illuminance sensor control unit 223 that outputs the drive control signal for controlling the illuminance sensor to be stopped when the LED is turned on and to be driven when the LED is turned off based on the acquired LED control signal.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a control technology for a digital rearview mirror that is placed and used inside a vehicle. [Background technology]

[0002] Patent Document 1 discloses an in-vehicle display device that is attached inside the vehicle cabin above and in front of the driver and has a display unit that displays images, an illuminance sensor that detects the brightness of the vehicle ceiling, and a brightness control means that controls the brightness of the display unit according to the brightness detected by the illuminance sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-001293 Summary of the Invention [Problem to be solved by the invention]

[0004] According to the in-vehicle display device of Patent Document 1, the brightness of the display unit can be controlled according to the detection result of an illuminance sensor that detects the brightness of the vehicle ceiling. However, when an infrared emitting device capable of emitting infrared rays, such as an occupant monitoring device, is mounted on the vehicle, there is a problem that the reflected light of the infrared rays emitted by the infrared emitting device is also detected by the illuminance sensor.

[0005] The present disclosure has been made to solve such problems, and aims to provide a control technology for a digital rearview mirror that can suppress detection of infrared rays emitted by an infrared irradiation device inside a vehicle equipped with an infrared irradiation device. [Means for solving the problem]

[0006] One aspect of a control device for a digital rearview mirror according to an embodiment of the present disclosure includes an LED control signal acquisition unit that acquires an LED control signal that controls the light emission of an LED provided in an infrared irradiation device arranged in the interior of the vehicle, an illuminance acquisition unit that acquires illuminance information, and an illuminance sensor control unit that outputs a drive control signal that controls the illuminance sensor to stop when the LED is on and to drive when the LED is off, based on the acquired LED control signal. [Effects of the Invention]

[0007] According to the control device for a digital rearview mirror according to an embodiment of the present disclosure, it is possible to suppress detection of infrared rays emitted by an infrared irradiating device. [Brief explanation of the drawings]

[0008] [Figure 1] 1A and 1B are diagrams illustrating an example of the configuration of a digital rearview mirror and an example of the configuration of a vehicle system including the digital rearview mirror and an occupant monitoring device. [Figure 2] FIG. 2 is a functional configuration diagram showing the functional configuration of a control device of the digital rearview mirror. [Figure 3] FIG. 3A is a diagram showing the light emission timing of an LED provided in the occupant monitoring device, and FIG. 3B is a diagram showing the drive timing of an illuminance sensor provided in the digital rearview mirror. [Figure 4A] FIG. 2 is a diagram illustrating an example of the hardware configuration of a control device. [Figure 4B] FIG. 2 is a diagram illustrating an example of the hardware configuration of a control device. DETAILED DESCRIPTION OF THE INVENTION

[0009] Various embodiments of the present disclosure will be described in detail below with reference to the drawings. In the drawings, identical or similar parts are designated by identical or similar reference numerals, and redundant explanations of such parts will be omitted. In addition, in this disclosure, the term "or" is used to mean an inclusive logical OR unless otherwise specified.

[0010] Embodiment 1 <Configuration> A digital rearview mirror according to a first embodiment of the present disclosure will be described with reference to FIG. 1. As shown in FIG. 1, a digital rearview mirror 2 is used together with an occupant monitoring device 1 as an infrared irradiation device. Both the digital rearview mirror 2 and the occupant monitoring device 1 are arranged in the interior of the same vehicle. As an example, the digital rearview mirror 2 is arranged on a rearview mirror arranged in the interior of the vehicle. As an example, the occupant monitoring device 1 is arranged on a steering column. Both the digital rearview mirror 2 and the occupant monitoring device 1 may be arranged in other positions. Examples of occupants include the driver and persons other than the driver.

[0011] (Occupant monitoring device) The occupant monitoring device 1 is a device for monitoring a vehicle occupant. As shown in FIG. 1, the occupant monitoring device 1 includes a control device 11, an image sensor 12, and an LED (light emitting diode) 13. The LED 13 is an LED that emits infrared light. The control device 11 controls the LED 13 to emit infrared light at a predetermined timing. The predetermined timing is, for example, a cycle of 30 Hz. The control device 11 controls the image sensor 12 to expose in synchronization with the predetermined timing. The control device 11 performs image processing on the infrared image of the occupant captured by the image sensor 12, and monitors the state of the occupant based on the results of the image processing.

[0012] Furthermore, the control device 11 outputs, via a wired or wireless connection, an LED control signal indicating the timing for controlling the light emission of the LED 13 to the digital rearview mirror 2. Note that the LED control signal may not only be a signal that directly controls the light emission of the LED 13, but also a signal that indirectly controls the light emission of the LED 13. In other words, when the light emission of the LED 13 is controlled based on a signal that controls the exposure of the image sensor 12, the signal that controls the exposure of the image sensor 12 indirectly controls the light emission of the LED 13 and is therefore included in the LED control signal.

[0013] (Digital rearview mirror) The digital rearview mirror 2 is a device for projecting an image behind the vehicle. The digital rearview mirror 2 is used in place of a conventional rearview mirror for checking the rear. An image of the area behind the vehicle is captured by an imaging device (not shown). As shown in FIG. 1 , the digital rearview mirror 2 includes an illuminance sensor 21, a control device 22, and a backlight 23. The backlight 23 constitutes a display (not shown) that the digital rearview mirror 2 includes.

[0014] The control device 22 of the digital rearview mirror 2 adjusts the light emission intensity of the backlight 23 based on the illuminance detected by the illuminance sensor 21. Specifically, the control device 22 adjusts the light emission intensity of the backlight 23 so that the light emission intensity increases as the illuminance increases.

[0015] Here, the infrared light emitted from the LED 13 of the occupant monitoring device 1 is reflected by the occupant or the interior of the vehicle. The reflected light is received not only by the image sensor 12 of the occupant monitoring device 1 but also by the illuminance sensor 21 of the digital rearview mirror 2. Therefore, when the illuminance sensor 21 detects the reflected light of the infrared light emitted from the LED 13, there is a problem that the light emission intensity of the backlight 23 becomes too strong. The digital rearview mirror 2 of the present disclosure solves this problem.

[0016] (illuminance sensor) The illuminance sensor 21 is a sensor that includes a light-receiving element for detecting infrared rays and detects the brightness inside the vehicle cabin. The illuminance sensor 21 generates a current according to the illuminance inside the vehicle cabin, i.e., according to the amount of infrared rays received. As an example, the illuminance sensor 21 outputs the generated analog current value as is to the control device 22 as illuminance information. The illuminance sensor 21 also converts the generated current value into a voltage value, converts the converted voltage value into digital data, and outputs the converted digital data to the control device 22 as illuminance information.

[0017] (Control device 22) The control device 22 is a device that performs various controls based on the illuminance information output from the illuminance sensor 21 or the LED control signal output from the occupant monitoring device 1. In order to perform various controls, the control device 22 has functional units as shown in Fig. 2. That is, the control device 22 includes an LED control signal acquisition unit 221, an illuminance acquisition unit 222, an illuminance sensor control unit 223, a backlight control unit 224, and a failure determination unit 225.

[0018] Furthermore, when the illuminance sensor 21 outputs illuminance information in the form of an analog current, the control device 22 includes a current-voltage converter 226 for converting the analog current value into a voltage value, and an AD converter 227 for converting the converted voltage value into digital data.

[0019] (LED control signal acquisition section) The LED control signal acquisition unit 221 is a functional unit that acquires an LED control signal output from the occupant monitoring device 1. The LED control signal acquisition unit 221 supplies the acquired LED control signal to the illuminance sensor control unit 223.

[0020] (Illuminance acquisition part) The illuminance acquisition unit 222 is a functional unit that acquires illuminance information indicating the illuminance inside the vehicle cabin based on the detection data of the illuminance sensor 21. When the illuminance sensor 21 outputs the illuminance information as digital data, the illuminance acquisition unit 222 acquires the illuminance information from the illuminance sensor 21. When the illuminance sensor 21 outputs the illuminance information as an analog current value, the illuminance acquisition unit 222 acquires the digital data output by the AD converter 227 as the illuminance information. The illuminance acquisition unit 222 supplies the acquired illuminance information to other functional units of the control device 22 via the bus.

[0021] (Illuminance sensor control unit) The illuminance sensor control unit 223 is a functional unit that controls the operation of the illuminance sensor 21 based on the LED control signal supplied from the LED control signal acquisition unit 221. The operation of the illuminance sensor control unit 223 will be described with reference to FIG.

[0022] FIG. 3A shows the light emission timing of the LED 13 included in the occupant monitoring device 1, and FIG. 3B shows the drive timing of the illuminance sensor 21 included in the digital rearview mirror 2. As shown in FIGS. 3A and 3B, the illuminance sensor control unit 223 controls the illuminance sensor 21 to stop operation when the LED 13 is turned on and to drive operation when the LED 13 is turned off. To perform this control, the illuminance sensor control unit 223 generates a drive control signal that stops operation of the illuminance sensor 21 at the rising edge of the LED control signal indicating the start of lighting and starts operation of the illuminance sensor 21 at the falling edge of the LED control signal indicating the end of lighting, and supplies the generated drive control signal to the illuminance sensor 21. During the lighting period of the LED 13, reflected light of infrared light emitted from the LED 13 enters the illuminance sensor 21, making it impossible to properly measure the illuminance. Therefore, to properly measure the illuminance, the illuminance sensor 21 may be stopped during the lighting period of the LED 13 so that illuminance information during the lighting period of the LED 13 is not acquired.

[0023] The illuminance sensor control unit 223 may be configured to monitor illuminance information. In this case, when the illuminance information indicates a strong light intensity at a constant cycle (for example, 30 Hz), the illuminance sensor control unit 223 may control the illuminance sensor 21 to stop operation when the light intensity is equal to or greater than a predetermined threshold, and to operate when the light intensity is less than the threshold.

[0024] (Backlight control unit) The backlight control unit 224 is a functional unit that adjusts the light emission intensity of the backlight 23 of the display of the digital rearview mirror 2 based on the illuminance information supplied from the illuminance acquisition unit 222 and the LED control signal supplied from the LED control signal acquisition unit 221. Specifically, the backlight control unit 224 acquires and stores illuminance information during the period when the LEDs 13 are turned off, and controls the backlight 23 to emit light in accordance with the stored illuminance information. In other words, during the period when the LEDs 13 are turned on, the backlight 23 is driven in accordance with the illuminance information acquired during the period when the LEDs 13 are turned off.

[0025] As described above, control may be performed to stop driving the illuminance sensor 21 during the lighting period of the LED 13. During the period in which the illuminance sensor 21 is stopped, the backlight control unit 224 may acquire and store illuminance information immediately before the illuminance sensor 21 is stopped, and control the backlight 23 according to the stored value.

[0026] The backlight control unit 224 may be configured to monitor illuminance information. In this case, when the illuminance information indicates a high light intensity with a constant period, the backlight control unit 224 acquires and stores the illuminance information if the light intensity is below a predetermined threshold, and controls the backlight 23 to emit light in accordance with the stored illuminance information. In other words, when the light intensity is equal to or greater than the threshold, it is considered that reflected light from the LED 13 is being received, and therefore, when the light intensity is equal to or greater than the threshold, the illuminance indicated by the illuminance information is not used.

[0027] In this way, when the illuminance information indicates a strong light intensity at a regular interval, the backlight control unit 224 acquires and stores the illuminance information when the light intensity is less than a predetermined threshold value, and controls the backlight 23 according to the stored value.

[0028] (Failure determination section) The malfunction determination unit 225 is a functional unit that determines whether the occupant monitoring device 1 is malfunctioning based on the LED control signal supplied from the LED control signal acquisition unit 221 or the illuminance information supplied from the illuminance acquisition unit 222. As one example, the malfunction determination unit 225 determines that the occupant monitoring device 1 is malfunctioning when it cannot acquire an LED control signal. As another example, the malfunction determination unit 225 determines that the occupant monitoring device 1 is malfunctioning when the illuminance information does not indicate a high light intensity at a constant period.

[0029] (backlight) The backlight 23 is a component that constitutes a display device (not shown). Under the control of a backlight control unit 224, the backlight 23 emits light toward a display panel provided in the display.

[0030] Next, with reference to Figures 4A and 4B, an example of the hardware configuration related to the functional units of the control device 22 will be described. Each function of the control device 22 is realized by a processing circuitry. The processing circuitry may be a dedicated processing circuit 100a as shown in Figure 4A, or a processor 100b that executes a program stored in a memory 100c as shown in Figure 4B.

[0031] When the processing circuitry is a dedicated processing circuit 100a, the dedicated processing circuit 100a may be, for example, a single circuit, a multiple circuit, a programmed processor, a parallel programmed processor, an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a combination thereof. The functions of the controller 22 may be implemented by separate processing circuits, or the functions of the controller 22 may be implemented together in a single processing circuit.

[0032] When the processing circuitry is a processor 100b, the functions of the control device 22 are realized by software, firmware, or a combination of software and firmware. The software and firmware are written as programs and stored in the memory 100c. The processor 100b realizes the functions of the control device 22 by reading and executing the programs stored in the memory 100c. Here, examples of the memory 100c include non-volatile or volatile semiconductor memories such as random access memory (RAM), read-only memory (ROM), flash memory, erasable programmable read-only memory (EPROM), and electrically erasable programmable read-only memory (EEPROM), as well as magnetic disks, flexible disks, optical disks, compact disks, minidisks, and DVDs.

[0033] It is also possible to implement some of the functions of the control device 22 using dedicated hardware, and other functions using software or firmware. In this way, the processing circuit can implement the functions of the control device 22 using hardware, software, firmware, or a combination of these.

[0034] It is possible to combine the embodiments, and to modify or omit each embodiment as appropriate. [Industrial Applicability]

[0035] The digital rearview mirror control device of the present disclosure can be used as a device for controlling a digital rearview mirror of a vehicle. [Explanation of symbols]

[0036] 1 Occupant monitoring device, 2 Digital rearview mirror, 11 Control device, 12 Image sensor, 13 LED, 21 Illuminance sensor, 22 Control device, 23 Backlight, 100a Processing circuit, 100b Processor, 100c Memory, 221 LED control signal acquisition unit, 222 Illuminance acquisition unit, 223 Illuminance sensor control unit, 224 Backlight control unit, 225 Failure determination unit, 226 Current-voltage converter, 227 AD converter.

Claims

1. an LED control signal acquisition unit that acquires an LED control signal that controls light emission of an LED included in an infrared irradiation device disposed in a vehicle interior; an illuminance acquisition unit that acquires illuminance information indicating the illuminance in the room; an illuminance sensor control unit that outputs a drive control signal based on the acquired LED control signal to control the illuminance sensor to stop during a lighting period of the LED and to drive during a lighting period of the LED; A control device for a digital rearview mirror.

2. the infrared irradiation device is an occupant monitoring device that monitors occupants of the vehicle, The digital rearview mirror control device according to claim 1.

3. a failure determination unit that determines that the occupant monitoring device is malfunctioning when the LED control signal cannot be acquired; The digital rearview mirror control device according to claim 2.

4. The digital rearview mirror control device according to any one of claims 1 to 3; the illuminance sensor; a backlight that illuminates the display panel of the display; A digital rearview mirror comprising: The control device further includes a backlight control unit that adjusts the emission intensity of the backlight based on the illuminance detected by the illuminance sensor. Digital rearview mirror.

5. When the illuminance information indicates a strong light intensity at a predetermined constant period, the illuminance sensor control unit controls the illuminance sensor to stop operation when the light intensity is equal to or greater than a predetermined threshold value, and to operate operation when the light intensity is less than the threshold value.

5. The digital rearview mirror according to claim 4.

6. The constant period is 30 Hz.

6. The digital rearview mirror according to claim 5.

7. the backlight control unit holds illuminance information during a period in which the illuminance sensor is driven, and adjusts the emission intensity of the backlight in accordance with the held illuminance information.

5. The digital rearview mirror according to claim 4.

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