JP2009282436A - Liquid crystal display device and liquid crystal display method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To maintain visibility for a viewer by changing display of a liquid crystal display part in accordance with a direction of a face of a viewer of the liquid crystal display part and distance. <P>SOLUTION: A viewer of a display device 24 is picked up by a lens 15 of a self-side arranged closing to the display device 24. A face of a person is extracted from a picked-up image signal, further a direction of the extracted face is calculated. Gradation of a display part 24 is changed based on a gradation conversion table in accordance with this calculated direction of the face. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device and a liquid crystal display method, and more particularly, to a liquid crystal display device and a liquid crystal display method that change display according to the distance and orientation with a viewer.

  When shooting with a digital camera or the like, the display image is difficult to see depending on the viewing angle characteristics of the liquid crystal depending on the angle at which the photographer views the liquid crystal monitor.

Patent Document 1 describes a display device that can automatically adjust the brightness of a display unit according to ambient brightness. According to this technology, the display area is brightened to improve visibility in bright outdoor areas, and the display area is dimmed in dark indoor areas to improve visibility and reduce backlight power consumption. It becomes possible to make it.
JP-A-9-65181

  However, in Patent Document 1, there is a problem in that control according to the distance and direction in which a person sees cannot be performed.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a liquid crystal display device and a liquid crystal display method capable of changing the display according to the orientation and distance of the face of the viewer.

  In order to achieve the above object, the liquid crystal display device according to claim 1 is a liquid crystal display device having a liquid crystal display unit, wherein a viewer who visually recognizes the liquid crystal display unit is imaged through a first lens. First image pickup means for converting the image signal into a first image signal; face detection means for detecting the face of the viewer from the first image signal; and display on the liquid crystal display unit based on a detection result of the face detection means. And control means for controlling.

  In this way, the orientation of the face of the viewer on the liquid crystal display unit is calculated, and the display on the liquid crystal display unit is controlled in accordance with the calculated face orientation, so that display with good visibility can be performed from any orientation. Can do.

  According to a second aspect of the present invention, in the liquid crystal display device according to the first aspect, the control unit controls the gradation of the liquid crystal display unit according to the orientation of the face detected by the face detection unit. To do.

  Thereby, even if it is a case where a liquid crystal display part is not seen from a front, visibility can be improved.

  According to a third aspect of the present invention, in the liquid crystal display device according to the second aspect, the control unit adjusts the gradation of the liquid crystal display unit based on a gradation table corresponding to the face orientation detected by the face detection unit. It is characterized by controlling.

  Thereby, the gradation can be easily controlled.

  4. The liquid crystal display device according to claim 1, wherein the control unit has a brightness and a floor of the liquid crystal display unit according to a face size detected by the face detection unit. It is characterized by controlling at least one of the keys.

  Thereby, even if it leaves | separates from a liquid crystal display part, visibility can be improved.

  According to a fifth aspect of the present invention, in the liquid crystal display device according to the fourth aspect, the control means increases the luminance as the face detected by the face detection means is smaller, or the smaller the face detected by the face detection means is. It is characterized by increasing the gradation.

  Thereby, even if it leaves | separates from a liquid crystal display part, visibility can be improved.

  6. The liquid crystal display device according to claim 1, wherein the control unit controls a display direction of the liquid crystal display unit according to a face direction detected by the face detection unit. It is characterized by doing.

  Thereby, the top and bottom can be correctly displayed from any direction.

  According to a seventh aspect of the present invention, in the liquid crystal display device according to any one of the first to sixth aspects, the first lens is disposed in the vicinity of the liquid crystal display unit.

  Thereby, the direction in which the viewer is looking at the liquid crystal display unit can be calculated correctly.

  The liquid crystal display device according to any one of claims 1 to 7, wherein when the face detection unit detects a plurality of viewers' faces, the selection unit selects a viewer as a reference. It is provided with.

  Thereby, when there are a plurality of viewers of the liquid crystal display unit, the display can be controlled in accordance with the selected viewers.

  The liquid crystal display device according to any one of claims 1 to 8, wherein the control unit is configured to display the liquid crystal display unit when the face detection unit does not detect the face of the viewer for a predetermined time. It is characterized by reducing power.

  Thereby, useless electric power can be reduced.

  The liquid crystal display device according to claim 9, wherein the control unit performs power reduction of the liquid crystal display unit when the liquid crystal display device is not operated for a predetermined time or longer. .

  As a result, power can be reduced when display on the liquid crystal display unit is not necessary.

  11. The liquid crystal display device according to claim 9, further comprising means for detecting a shake of the liquid crystal display device, wherein the control means is configured to detect the shake when the shake is not detected for a predetermined time or more. It is characterized by reducing power consumption.

  As a result, power can be reduced when display on the liquid crystal display unit is not necessary.

  12. The liquid crystal display device according to claim 9, wherein the power reduction of the liquid crystal display unit is non-display of the liquid crystal display unit or backlight off. To do.

  Thereby, the power reduction of a liquid crystal display part can be performed easily.

  According to a thirteenth aspect of the present invention, in the liquid crystal display device according to any one of the first to twelfth aspects, a second imaging unit that captures an image of a subject through the second lens and converts it into a second image signal is provided. It is characterized by that.

  Thereby, when picking up an image of a subject, it is possible to perform liquid crystal display that is easy for a viewer to see.

  In order to achieve the object, the liquid crystal display method according to claim 14, wherein an imaging step of imaging a viewer who visually recognizes the liquid crystal display unit and converting it into an image signal, and detecting the face of the viewer from the image signal. And a control step of controlling display of the liquid crystal display unit based on a detection result of the face detection step.

  In this way, the orientation of the face of the viewer on the liquid crystal display unit is calculated, and the display on the liquid crystal display unit is controlled in accordance with the calculated face orientation, so that display with good visibility can be performed from any orientation. Can do.

  According to the present invention, the orientation of the face of the viewer of the liquid crystal display unit is calculated, and the display of the liquid crystal display unit is controlled according to the calculated orientation of the face. Can be done.

  The best mode for carrying out the present invention will be described below with reference to the accompanying drawings.

<First Embodiment>
FIG. 1 is a block diagram showing an electrical configuration of the mobile phone 1 according to the first embodiment. In this block diagram, the digital camera unit 10 is mainly shown, and constituent elements relating to telephone calls and transmission / reception of e-mails are omitted.

  As shown in the figure, the mobile phone 1 according to the present embodiment includes a counterpart (subject) lens 11, a motor driver 12, a first CCD 13, a first analog front end (AFE) 14, a self-side ( Photographer side) lens 15, second CCD 16, second analog front end unit (AFE) 17, CPU 18, face extraction IC 19, orientation calculation unit 20, memory 21, external memory 22, signal processing IC 23, display device 24, etc. It is configured with.

  Each unit operates under the control of the CPU 18, and the CPU 18 controls each unit of the digital camera unit 10 by executing a predetermined control program.

  The motor driver 12 drives the zoom lens and focus lens of the counterpart lens 11 based on a command from the CPU 18 to perform zooming and focusing of the counterpart lens 11.

  The counterpart lens 11 transmits the subject light and causes the first CCD 13 to receive the light.

  The first CCD 13 receives the subject light transmitted by the counterpart lens 11 and converts it into an image signal. The image signal output from the CCD 13 is an analog signal, and this analog image signal is input to the AFE 14 and converted into a digital image signal having gradation values indicating R, G, and B densities for each pixel, and the CPU 18 Is input. The CPU 18 stores the digital image signal in the memory 21.

  As shown in FIG. 2, the counterpart lens 11 and the own lens 15 are arranged on the front and back of the housing so as to capture directions different from each other by 180 °, and when the counterpart lens 11 faces the subject, the own lens 15 is arranged so that the photographer 100 can be imaged. The own lens 15 transmits light from the photographer 100 and causes the second CCD 16 to receive the light. Here, the orientation of the face when the photographer 100 looks at the own lens 15 and the orientation of the face of the photographer 100 when the photographer 100 looks at the display device 24 are substantially the same. The own lens 15 is arranged so as to be close to the display device 24.

  The second CCD 16 receives the photographer light transmitted by the own lens 15 and converts it into an image signal. This image signal is converted into a digital signal by the AFE 17 and input to the CPU 18. The CPU 18 also stores this image signal in the memory 21.

  The memory 21 is used as a storage area for storing the captured image as described above, and also as a work area for the CPU 18 to load a program from a ROM (not shown).

  The signal processing IC performs predetermined processing on the image signal stored in the memory 21 and converts the image signal into a signal of a format for storing in the external memory 22 or a signal for display on the display device 24.

  The external memory 22 is configured to be detachable from the mobile phone 1 and records image signals as described above.

  The display device 24 is a liquid crystal display provided with a backlight. The display device 24 displays a through image when the mobile phone 1 takes an image, displays an image stored in the external memory 22, and allows the user to set the functions of the mobile phone 1. GUI display when performing is performed. Further, as will be described later, the display gradation can be changed by a command from the CPU 18.

  The face extraction IC 19 analyzes the image signal captured by the own lens 15 stored in the memory 21, extracts the face of the photographer 100 in the image, and outputs the result to the CPU 18. The orientation calculation unit 20 calculates the orientation of the face relative to the mobile phone 1 based on the positions of the eyes, nose, and mouth in the face for the face in the image extracted by the face extraction IC 19. For example, the orientation in the horizontal direction is calculated as 0 ° when the face is directly in front of the mobile phone 1, and 90 ° when the face is in front, and the face is directly in the vertical direction. Is calculated as 0 ° when the head is facing, and 90 ° when facing the top or bottom.

  FIG. 3 is a diagram showing the face of the photographer 100 captured by the second CCD 16 through the own lens 15. 4 is a list of face orientations calculated by the orientation calculation unit based on the output of the face extraction IC 19 by extracting the face based on the output signal of the CCD 16 shown in FIG.

  As shown in FIG. 3, for example, the face a is present at the upper left of the imaging range of the second CCD 16, and the display device 24 is viewed from the upper left direction. The face extraction IC 19 extracts the face, and the orientation calculation unit 20 calculates the orientation of the extracted face a. As shown in FIG. 4, the face orientation calculated for the face a is 45 ° to the right and 45 ° to the bottom.

  Next, gradation correction processing of the display device 24 in the mobile phone 1 will be described with reference to FIG.

  First, the face extraction IC 19 extracts a person's face from the image signal captured by the second CCD 16 via the own lens 15, and the CPU 18 determines whether or not the face has been extracted (step S1). .

  If no face is extracted, the process ends. When the face is extracted, the orientation calculation unit 20 calculates the orientation of the extracted face (step S2), compares the calculated face orientation with the current gradation setting of the display device 24, and It is determined whether or not the optimum gradation setting is set (step S3).

  FIG. 6 shows the relationship between the input image signal and the gradation when viewed from the front. As shown in the figure, the gradation indicated by the solid line is the optimum gradation when viewed from the front, and the gradation indicated by the dotted line is an optimum gradation according to the face direction of the photographer 100. is there. As described above, the mobile phone 1 includes a plurality of gradation conversion tables in the memory 21, and the display that is easy for the photographer 100 to view by using the optimum gradation conversion table according to the calculated face orientation. I do.

  If the optimum gradation setting is set, the process is terminated. If the optimum gradation setting is not set, a gradation conversion table corresponding to the calculated face orientation is read from the memory 21 and gradation conversion is performed (step S4).

  In this way, by calculating the direction in which the photographer 100 is looking at the display device 24 and performing gradation conversion in accordance with the calculated direction, it is possible to maintain visibility without black crushing or overexposure. Become.

<Second Embodiment>
FIG. 7 is a block diagram illustrating an electrical configuration of the mobile phone 1 according to the second embodiment. In addition, the same code | symbol is attached | subjected to the part which is common in the block diagram shown in FIG. 1, and the detailed description is abbreviate | omitted. 1 is different from the block diagram shown in FIG. 1 in that a distance calculation unit 25 is provided instead of the direction calculation unit 20.

  The distance calculation unit 25 calculates the distance between the photographer 100 and the display device 24 based on the face size extracted by the face extraction IC 19. As shown in FIG. 8, the face extracted from the image signal imaged through the self-side lens 15 is small when it is far from the display device 24, and the face extracted is large when it is close to the display device 24. It is. In this way, the distance between the photographer 100 and the display device 24 can be calculated by comparing the size of the extracted face with the standard face size.

  Next, tone correction processing of the display device 24 according to the second embodiment will be described with reference to FIG.

  First, the face extraction IC 19 extracts a person's face from the image signal captured by the second CCD 16 via the own lens 15 and the CPU 18 determines whether or not a face has been extracted (step S11). .

  If no face is extracted, the process ends. When the face is extracted, the distance calculation unit 25 calculates the distance between the extracted face and the display device 24 (step S12). Further, the calculated face distance is compared with the brightness and gradation setting of the current display device 24, and it is determined whether or not the optimum brightness and gradation are set (step S13).

  FIG. 10A shows the relationship between the calculated distance and the optimal brightness of the display device 24. As shown in the figure, the brightness of the display device 24 becomes easier to see as the distance increases, so the backlight brightness of the display device 24 is increased according to the distance.

  FIG. 10B shows the relationship between the input image signal and the gradation when viewed from the front. Similar to FIG. 6, the gradation indicated by the solid line is the optimum gradation when viewed from the front. As shown in the figure, the gradation is lowered when the calculated distance is small, and the gradation is raised when the distance is large.

  As described above, the mobile phone 1 includes a plurality of luminance change tables and gradation conversion tables in the memory 21.

  If the optimum gradation setting and backlight setting are set, the process is terminated. If the optimum gradation setting and backlight setting are not set, the luminance and gradation are changed according to the calculated distance (step S14).

  In this way, the distance between the photographer 100 and the display device 24 is calculated, and the luminance can be changed and the gradation conversion is performed according to the calculated distance, so that visibility can be maintained.

<Third Embodiment>
FIG. 11 is a block diagram illustrating an electrical configuration of the mobile phone 1 according to the third embodiment. In addition, the same code | symbol is attached | subjected to the part which is common in the block diagram shown in FIG. 1, and the detailed description is abbreviate | omitted. 1 is different from the block diagram shown in FIG. 1 in that a direction calculation unit 26 is provided instead of the direction calculation unit 20.

  The direction calculation unit 26 calculates the face direction extracted by the face extraction IC 19. As shown in FIG. 12, the face direction indicates from which direction on the display device 24 the photographer 100 is looking. If the face direction in FIG. 12A is 0 °, the face direction in FIG. 12B can be expressed as 225 °.

  Next, the display direction adjustment processing of the display device 24 according to the third embodiment will be described with reference to FIG.

  As before, the face extraction IC 19 extracts the face of the person from the image signal captured by the second CCD 16 via the own lens 15 and the CPU 18 determines whether or not the face has been extracted ( Step S21).

  If no face is extracted, the process ends. When the face is extracted, the direction calculation unit 26 calculates the extracted face direction (step S22). Further, the calculated face direction is compared with the current display direction of the display device 24 to determine whether or not the display direction is optimal (step S23).

  If the display direction is already optimal, the process is terminated as it is. When the display direction is not optimal, the display direction of the display device 24 is changed based on the calculated face direction (step S24).

  For example, when a face is detected as shown in FIG. 12A from an image signal captured through the own lens 15, the display direction of the display device 24 is controlled as shown in FIG. When a face is detected as shown in FIG. 12B, the display direction of the display device 24 is controlled as shown in FIG. 13B. In this way, by changing the display direction of the display device 24 in accordance with the direction in which the photographer 100 views the display device 24, the photographer 100 can visually recognize the correct screen on the top and bottom no matter what direction the display device 24 is viewed. It becomes possible to do.

  In the first embodiment, the gradation is changed according to the orientation of the face, in the second embodiment, the brightness and gradation are changed according to the distance from the face, and in the third embodiment, the face is changed. Although the display direction is changed according to the direction, the gradation, luminance, and direction may be changed by combining these. With this configuration, the visibility of the display device 24 can be further improved.

<Fourth embodiment>
FIG. 15 is a block diagram illustrating an electrical configuration of the mobile phone 1 according to the fourth embodiment. In addition, the same code | symbol is attached | subjected to the part which is common in the block diagram shown in FIG. 1, and the detailed description is abbreviate | omitted. 1 is different from the block diagram shown in FIG. 1 in that a photographer selection unit 27 is provided.

  The photographer selection unit 27 is an operation member for the user to select the photographer 100 when the face extraction IC 19 extracts a plurality of faces from the image signal captured through the self-side lens 15. A key is suitable.

  Next, gradation correction processing of the display device 24 according to the fourth embodiment will be described with reference to FIG.

  As before, the face extraction IC 19 extracts the face of the person from the image signal captured by the second CCD 16 via the own lens 15 and the CPU 18 determines whether or not the face has been extracted ( Step S31).

  If no face is extracted, the process ends. If a face is extracted, it is determined whether there are a plurality of extracted faces (step S32). When there is one extracted face, the process proceeds to step S34, where the orientation of the face extracted by the orientation calculating unit 20 is calculated, and the gradation correction of the display device 24 is performed according to the calculated orientation.

  When there are a plurality of extracted faces, the image signal via the own lens 15 is read from the memory 21 and displayed on the display device 24. As shown in FIG. 17, the display device 24 displays a face detection frame 101 for each of the extracted faces. While viewing this display, the user uses the photographer selection unit 27 to select the photographer 100. Of the plurality of face detection frames 101, only one is a thick frame. By operating the photographer selection unit 27, the thick frames move sequentially. The user operates the photographer selection unit 27 so that the face frame of the photographer 100 becomes a thick frame (step S33). The thick frame may be a frame having the same thickness and different colors.

  When the photographer 100 is selected, the orientation of the face extracted by the orientation calculator 20 is calculated, and gradation correction of the display device 24 is performed according to the calculated orientation (step S34).

  As described above, even when a plurality of faces are extracted from the self-side lens 15, visibility to the photographer 100 can be maintained by selecting the photographer 100. In the present embodiment, the gradation is changed according to the orientation of the face of the selected photographer 100. However, the brightness and gradation may be changed according to the distance from the face of the selected photographer 100. The display direction may be changed according to the face direction of the selected photographer 100, or these controls may be combined.

<Fifth embodiment>
Since the mobile phone 1 according to the present invention includes the own lens 15 and is configured to detect the face of the photographer 100, it is also possible to detect that the photographer 100 is absent.

  FIG. 18 is a flowchart showing processing for confirming the existence of the photographer 100. When the CPU 18 determines that the mobile phone 1 has not been operated for a certain period of time (step S41), the CPU 18 causes the face extraction IC to perform face extraction from the image signal captured through the own lens 15, and whether or not there is a face. (Step S42).

  If a face is extracted, the process ends. When the face is not extracted, the CPU 18 sets the display device 24 to the liquid crystal power saving mode (step S43). In the liquid crystal power saving mode, the display of the display device 24 may be turned off, or the backlight of the display device 24 may be turned off.

  As described above, when no operation is performed for a certain period of time and no face is extracted, it is determined that no one is looking at the display device 24, and the power consumption of the display device 24 can be reduced, thereby reducing power consumption. It becomes.

  When the camera function of the mobile phone 1 has a camera shake correction function, camera shake may be detected to trigger detection of the absence of the photographer 100.

  FIG. 19 is a block diagram showing an electrical configuration when the camera function of the mobile phone 1 has a camera shake correction function. In addition, the same code | symbol is attached | subjected to the part which is common in the block diagram shown in FIG. 1, and the detailed description is abbreviate | omitted. 1 is different from the block diagram shown in FIG. 1 in that a camera shake correction IC 28 is provided.

  The camera shake correction IC 28 can detect the shake of the mobile phone 1. When a shake is detected during imaging, the image sensor is moved in accordance with the amount and direction of the shake to correct the shake of the captured image. To do. Further, the result of the detected shake can be output to the CPU 18.

  FIG. 20 is a flowchart showing processing for confirming the existence of the photographer 100 when the camera shake correction IC 28 is provided.

  First, the camera shake correction IC 28 detects a shake of the mobile phone 1. The shake detection may be performed continuously or may be performed every predetermined time. If the CPU 18 determines from the output of the camera shake correction IC 28 that the camera 18 has not detected a shake for a certain period of time (step S51), the CPU 18 causes the face extraction IC to perform face extraction from the image signal captured through the own lens 15. Then, the presence or absence of a face is determined (step S52).

  If a face is extracted, the process ends. When the face is not extracted, the CPU 18 sets the display device 24 to the liquid crystal power saving mode (step S43). In the liquid crystal power saving mode, the display of the display device 24 may be turned off, or the backlight of the display device 24 may be turned off.

  As described above, when no blur is detected for a certain period of time and no face is extracted, it is determined that no one is looking at the display device 24 and power is saved in the display device 24, thereby reducing power consumption. It becomes possible.

FIG. 1 is a block diagram showing an electrical configuration of the mobile phone 1 according to the first embodiment. FIG. 2 is a diagram illustrating an arrangement of the own lens 15, the display device 24, and the photographer 100. FIG. 3 is a diagram showing the face of the photographer 100 captured by the second CCD 16 through the own lens 15. FIG. 4 is a list of face orientations calculated by the orientation calculation unit for the faces shown in FIG. FIG. 5 is a flowchart illustrating the tone correction processing of the display device 24 according to the first embodiment. FIG. 6 is a diagram showing the relationship between the input image signal and the gradation when viewed from the front. FIG. 7 is a block diagram illustrating an electrical configuration of the mobile phone 1 according to the second embodiment. It is a figure shown about the difference in the size of the extracted face according to the distance of the photographer 100 and the display apparatus 24. FIG. FIG. 9 is a flowchart illustrating the tone correction processing of the display device 24 according to the second embodiment. FIG. 10 is a diagram showing the optimum luminance and gradation according to the calculated distance. FIG. 11 is a block diagram illustrating an electrical configuration of the mobile phone 1 according to the third embodiment. FIG. 12 is a diagram illustrating the direction of the extracted face. FIG. 13 is a diagram illustrating the change of the display direction according to the extracted face direction. FIG. 14 is a flowchart illustrating a display direction adjustment process of the display device 24 according to the third embodiment. FIG. 15 is a block diagram illustrating an electrical configuration of the mobile phone 1 according to the fourth embodiment. FIG. 16 is a flowchart illustrating a photographer selection process according to the fourth embodiment. FIG. 17 is a diagram showing a plurality of faces extracted from an image signal captured through the own lens 15. FIG. 18 is a flowchart showing power saving mode input processing of the display device 24. FIG. 19 is a block diagram showing an electrical configuration of the fifth embodiment. FIG. 20 is a flowchart showing power saving mode input processing of the display device 24 when the camera shake correction IC is used.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Mobile phone, 11 ... Opposite side lens, 12 ... Motor driver, 13 ... 1st CCD, 14 ... 1st analog front end, 15 ... Own side lens, 16 ... 2nd CCD, 17 ... 2nd Analog front end, 18 ... CPU, 19 ... Face extraction IC, 20 ... Direction calculation unit, 21 ... Memory, 22 ... External memory, 23 ... Signal processing IC, 24 ... Display device, 25 ... Distance calculation unit, 26 ... Direction calculation , 27 ... Photographer selection unit, 100 ... Photographer, 101 ... Face detection frame

Claims (14)

In a liquid crystal display device having a liquid crystal display unit,
A first imaging means for imaging a viewer who visually recognizes the liquid crystal display unit through a first lens and converting the image into a first image signal;
Face detecting means for detecting the face of the viewer from the first image signal;
Control means for controlling the display of the liquid crystal display unit based on the detection result of the face detection means;
A liquid crystal display device comprising:   The liquid crystal display device according to claim 1, wherein the control unit controls a gradation of the liquid crystal display unit according to a face orientation detected by the face detection unit.   The liquid crystal display device according to claim 2, wherein the control unit controls the gradation of the liquid crystal display unit based on a gradation table corresponding to the face orientation detected by the face detection unit.   The said control means controls at least one of the brightness | luminance and gradation of the said liquid crystal display part according to the size of the face which the said face detection means detected. Liquid crystal display device.   5. The liquid crystal display device according to claim 4, wherein the control unit increases the luminance as the face detected by the face detection unit decreases, or increases the gradation as the face detected by the face detection unit decreases. .   The liquid crystal display device according to claim 1, wherein the control unit controls a display direction of the liquid crystal display unit in accordance with a face direction detected by the face detection unit.   The liquid crystal display device according to claim 1, wherein the first lens is disposed in proximity to the liquid crystal display unit.   8. The liquid crystal display device according to claim 1, further comprising a selection unit that selects a reference viewer when the face detection unit detects the faces of a plurality of viewers. 9.   9. The liquid crystal display device according to claim 1, wherein the control unit reduces power of the liquid crystal display unit when the face detection unit does not detect the face of the viewer for a predetermined time. .   The liquid crystal display device according to claim 9, wherein the control unit reduces power of the liquid crystal display unit when the liquid crystal display device is not operated for a predetermined time or more. Means for detecting blur of the liquid crystal display device;
The liquid crystal display device according to claim 9, wherein the control unit reduces the power of the liquid crystal display unit when no blur is detected for a predetermined time.   The liquid crystal display device according to claim 9, wherein the power reduction of the liquid crystal display unit is non-display of the liquid crystal display unit or backlight off.   13. The liquid crystal display device according to claim 1, further comprising: a second image pickup unit that picks up an image of a subject through a second lens and converts the image into a second image signal. An imaging step of imaging a viewer viewing the liquid crystal display unit and converting it into an image signal;
A face detection step of detecting the face of the viewer from the image signal;
A control step of controlling the display of the liquid crystal display unit based on the detection result of the face detection step;
A liquid crystal display method comprising:

Images