JP2007163816A - Display device and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device which is provided with a camera on the rear surface side of a transmission type liquid crystal panel, is thinned, and suppresses flicker of a display screen. <P>SOLUTION: The display device 1 is provided with: a liquid crystal display part 3 provided with the transmission type liquid crystal panel 3a and displaying inputted image data; a backlight unit 5 disposed on the rear surface side of the liquid crystal display part 3; a camera unit 4 disposed on the rear surface side of the backlight unit 5; a hole 5a formed in the backlight unit 5 in a position corresponding to the position of a lens 4a of the camera unit 4; and a shutter controlling part 10 forming image data by which display of a region 6 in the vicinity of the hole 5a is made to be off-display where light from a front surface side is transmitted for every predetermined period based on image data inputted from an external part and outputting the image data to the liquid crystal display part 3 and outputting the image data inputted from the external part as it is to the liquid crystal display part 3 in a period except the predetermined period. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a display device, and more particularly to a display device integrated with a camera and a control method thereof.

  2. Description of the Related Art Conventionally, in videophone systems, video conference systems, and the like, various attempts have been made to place a camera on a display device in order to converse with a person displayed on the display device.

  For example, Patent Document 1 discloses a video display imaging device in which a small camera is suspended from the upper part of a display device in accordance with the user's line-of-sight position. Patent Document 2 discloses an image display device with a built-in camera that captures an image of a user by installing a camera on the back of a reflective liquid crystal display device and using a half mirror as a reflective plate.

Further, Patent Document 3 discloses a face-to-face conversation apparatus that enables a front-side image to be captured by a video camera installed at the back of the transmissive liquid crystal screen by turning the transmissive liquid crystal screen off at predetermined intervals. It is disclosed.
Further, Patent Document 4 discloses a camera-integrated display device including a hole in a polarizing plate on the back side of a transmissive liquid crystal display device and a camera that captures a user's image through the hole.
JP-A-11-284970 (paragraphs 0015 to 0016, FIG. 1) JP 2003-259321 A (paragraphs 0010 to 0013, FIG. 1) Japanese Utility Model Publication No. 64-11076 Japanese Patent No. 3387136 (paragraphs 0011 to 0014, FIG. 1)

However, since the camera-holding type image display device described in Patent Document 1 is arranged on the front surface of the display device, even if the camera-holding member is made of a highly transmissive material, the portion Display is distorted, accurate display cannot be performed, and the user feels uncomfortable.
In addition, since the camera built-in type image display device described in Patent Document 2 uses a reflective liquid crystal, it cannot be used in a dark place, and the use of a half mirror as a reflector reduces the reflectance of incident light. There is a problem that the saturation of the liquid crystal display portion is lowered.

In the face-to-face conversation device described in Patent Document 3, the entire surface of the liquid crystal screen is turned off at predetermined intervals, and the video camera picks up the image on the front side during that time, so that flickering of the liquid crystal screen occurs. There was a problem.
Furthermore, the camera-integrated display device described in Patent Document 4 is provided with a hole in the polarizing plate on the back side, so that the illuminance unevenness of light that passes through the polarizing plate on the back side from the backlight and enters the liquid crystal panel is uneven. It is necessary to suppress the occurrence of Therefore, it is necessary to provide a predetermined interval between the polarizing plate on the back side and the liquid crystal panel, and it is difficult to produce a thin camera-integrated display device.

  Accordingly, the present invention provides a display device that solves the above-described problems, can be thinned with a camera on the back of a transmissive liquid crystal panel, and can suppress flicker in the entire screen, and a control method thereof. With the goal.

  A display device according to the present invention, which has been made to solve the above problems, includes a transmissive liquid crystal panel, a liquid crystal display unit that displays input image data, and a backlight unit disposed on the back side of the liquid crystal display unit And a camera unit arranged on the back side of the backlight unit, a hole formed in the backlight unit in accordance with the position of the lens of the camera unit, and a region near the hole based on image data input from the outside Is generated every predetermined time and output to the liquid crystal display unit, and image data input from the outside is output to the liquid crystal display unit outside the predetermined time. And a shutter control unit.

As described above, the thus configured display device according to the present invention provides a predetermined hole between the liquid crystal panel and the backlight unit installed on the back side thereof by diffracting light around the hole by providing the hole only in the backlight unit. There is no need to install them at intervals. In addition, flickering of the entire screen can be suppressed by controlling blinking of only the region near the hole in the display region of the liquid crystal display unit.
Other aspects of the present invention will be described in the embodiments described later.

  According to the display device and the control method thereof according to the present invention, it is possible to implement a thin camera-equipped display device that is almost unaware of the flicker of the liquid crystal screen. Further, since the lens opening of the camera can be enlarged, the S / N ratio of the video signal output from the camera can be increased.

  Next, a display device with a built-in camera according to an embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

(Configuration of display device with built-in camera)
FIG. 1 is a diagram showing a configuration of a display device with a built-in camera according to the present embodiment, in which (a) is a front view of the display device with a built-in camera, and (b) is a partial longitudinal sectional view thereof. As shown in FIG. 1A, the camera built-in display device 1 according to the present embodiment is installed in a liquid crystal display unit 3 and a back part of the liquid crystal display unit 3 inside a housing 2 formed of resin or the like. And a camera unit 4. A backlight unit 5 (see FIG. 1B) is interposed between the liquid crystal display unit 3 and the camera unit 4. Further, the camera built-in display device 1 has a shutter control unit (not shown) (see FIG. 2) that controls the display of the liquid crystal display unit 3 and the operation of the camera unit 4.
In the following description, the side on which the camera-equipped display device 1 displays an image (left side in FIG. 1B) is referred to as the front side, and the opposite side (right side in FIG. 1B) is referred to as the back side. .

(Liquid crystal display)
As shown in FIG. 1B, the liquid crystal display unit 3 includes, for example, a TSTN (Triple Super Twisted Nematic) type liquid crystal panel 3a, a front polarizing plate 3b arranged on the front side, and a back side arranged on the back side. It is configured to be sandwiched between the polarizing plates 3c. Further, the liquid crystal display unit 3 includes a liquid crystal driving circuit (not shown) which is a driving circuit for the liquid crystal panel 3a. When the display image data is acquired from a computer (not shown) or the like connected to the outside, the liquid crystal display unit 3 drives the liquid crystal panel 3a to display an image corresponding to the display image data.

In addition, a shutter area 6 which is an area where the display of the liquid crystal display section 3 blinks is set by an aperture data switching section (see FIG. 2) which will be described later, in the approximate center of the liquid crystal display section 3. Light from the front side enters the camera unit 4 via the region 6.
The size of the shutter region 6 is set in advance according to the size of the lens 4a of the camera unit 4, and is desirably set to a minimum size that does not affect the captured image. A detailed description of the shutter area 6 will be given later.

(Camera unit)
The camera unit 4 includes a solid-state image sensor (not shown) such as a CCD (Charge Coupled Device) element or a CMOS (Complementary Metal Oxide Semiconductor) element, and a lens 4a that focuses light incident from the front side on the solid-state image sensor. Configured as a unit. The camera unit 4 includes a camera control circuit (not shown) that outputs a signal imaged by the solid-state imaging device as camera imaging data, images the light incident from the front side, and outputs camera imaging data.
Note that it is desirable to use a Fresnel lens as the lens 4 a of the camera unit 4. By using a Fresnel lens as the lens 4a, a thin lens with a large angle of view can be realized. Thereby, it becomes possible to further reduce the thickness of the display device 1 with a built-in camera. In addition to the Fresnel lens, it is of course possible to apply an aspherical lens made of glass or plastic.
Further, in order to suppress unevenness in the illuminance of the display screen due to diffraction of light emitted from the backlight unit, it is desirable that the diameter of the lens 4a is smaller than about 10 mm.

(Backlight unit)
The backlight unit 5 irradiates light from the cold cathode tube, which is a light source, an organic electroluminescent sheet, an LED (Light Emitting Diode), and the like toward the front side with light that is nearly non-directional. It is configured to
In addition, a small hole 5 a for taking in light from the front side through the liquid crystal display unit 3 is formed in the approximate center of the backlight unit 5 corresponding to the rear part of the shutter region 6 of the liquid crystal display unit 3. Yes. The lens 4a of the camera unit 4 is disposed on the back side of the hole 5a.

Further, as shown in FIG. 1B, the front surface side of the hole 5a is formed so as to expand in a taper shape, and a region near the taper of the hole 5a is a back surface where the hole 5a of the liquid crystal display unit 3 is disposed. It functions as a light guide 5b for uniformly diffusing the light of the backlight unit 5 in the part.
By this light guide 5b, the light irradiated from the backlight unit 5 is favorably diffused into the shutter region 6 of the liquid crystal display unit 3, and uneven illuminance can be suppressed.

(Block of the shutter control unit)
Next, FIG. 2 is an example of a schematic block diagram of a shutter control unit of the display device 1 with a built-in camera according to the present embodiment. As shown in FIG. 2, when the shutter control unit 10 of the camera-equipped display device 1 acquires a timing signal from the camera control unit 12, only the shutter region 6 of the display region of the liquid crystal display unit 3 is light from the front side. If the aperture data switching unit 11 that generates display image data that is displayed in a transparent manner (hereinafter referred to as OFF display) and camera operation request information that requests the operation of the camera unit 4 are acquired from an external personal computer or the like, Based on the clock, a timing signal is transmitted to the aperture data switching unit 11 at every predetermined timing (for example, 1/30 sec), and a camera drive signal is transmitted to the camera unit 4 connected to the camera control unit 12 at the same timing. And a camera control unit 12 for transmitting the information.
Note that the aperture data switching unit 11 is connected to the liquid crystal display unit 3 and delivers display image data acquired from the outside to the liquid crystal display unit 3 as it is except when a timing signal is received.
Display image data is input from an external personal computer or the like via a display cable, and camera operation request information and camera imaging data are input to or from a personal computer via a USB (Universal Serial Bus) cable or the like. Is output. The display image data may be a video signal from a personal computer or the like, or a video signal from a television or a DVD (Digital Versatile Disc) player.

(Operation of display device with built-in camera)
Next, the operation of the shutter control unit 10 of the camera built-in display device 1 will be described in detail with reference to the flowchart illustrating the operation of the shutter control unit 10 shown in FIG. 3 (see FIGS. 1 and 2 as appropriate). ).
For example, the display image data input from an external device such as a personal computer is 60 frames per second (60 fps), and the light transmission interval from the front side to the camera unit 4 in the shutter region 6 is It is assumed that 1/15 sec. That is, the number of frames of display image data in the shutter area is 45 fps. The light transmission interval is set in advance and recorded in the camera control unit 12. Further, it is assumed that the position information of the area to be the shutter area 6 in the display area of the liquid crystal display section 3 is also preset and recorded in the aperture data switching section 11.
The value of the light transmission interval described above can also be changed from a personal computer connected to the display device 1 with a built-in camera.
In order to suppress flicker in the shutter area 6, it is desirable to secure the number of frames of the display image in the shutter area 6 to about 10 fps or more.

  First, when the display image data is input from an external personal computer or the like, the shutter control unit 10 of the camera-equipped display device 1 causes the aperture data switching unit 11 to input the input display image data to the liquid crystal display unit 3 as it is. Deliver (step S101). The liquid crystal display unit 3 that has acquired the display image data displays an image corresponding to the display image data.

Next, the camera control unit 12 of the shutter control unit 10 uses an internal clock to generate a timing generation circuit (not shown) prepared in an external device such as a personal computer or the display device 1 with a built-in camera every predetermined time (1/15 sec). It is determined whether the camera operation request information transmitted from is detected (step S102). If the camera operation request information is not detected (“No” in step S102), the process returns to step S101, and the shutter control unit 10 directly inputs the input display image data to the liquid crystal display unit 3. Send.
Here, since the determination whether or not the camera operation request information is detected is performed every 1/15 sec, the display image data input to the aperture data switching unit 11 every 1/60 sec is determined in step S102. During the period in which the operation is not performed, it is transmitted to the liquid crystal display unit 3 as it is in step S101.

  On the other hand, when camera operation request information is detected in step S102 (“Yes” in step S102), the camera control unit 12 transmits a timing signal to the aperture data switching unit 11 (step S103). Receiving this timing signal, the aperture data switching unit 11 generates shutter image data in which the area corresponding to the shutter area 6 of the input display image data is turned off, and transmits it to the liquid crystal display unit 3 (step S104). ). The liquid crystal display unit 3 that has received the shutter image data displays an image in which only the shutter area 6 is displayed off from the display image data corresponding to the shutter image data (in a state where the shutter is opened). Thereby, the light from the front side passes through the shutter region 6 of the liquid crystal display unit 3 and enters the camera unit 4.

  Then, the camera control unit 12 transmits a camera drive signal to the camera unit 4 (step S105), and the camera unit 4 that has received this camera drive signal passes through the shutter region 6 of the liquid crystal display unit 3 and enters the front surface. An image of the subject on the side is captured and output to an external device as camera imaging data. The camera drive signal transmitted by the camera control unit 12 is transmitted when the camera operation request information is input regardless of the determination in step S102.

  The camera drive signal transmitted from the camera control unit 12 to the camera unit 4 can be transmitted every 1/15 sec in synchronization with the timing signal transmitted to the aperture data switching unit 11. In this case, the camera unit captures an image of the subject at an interval of 1/15 sec by a camera drive signal synchronized with the timing signal.

As described above, the camera built-in display device 1 according to the present embodiment described above provides the following effects.
First, the depth of the camera-equipped display device 1 can be reduced. Moreover, since the structure of the display device 1 with a built-in camera is simple, the manufacturing cost of the display device 1 with a built-in camera can be suppressed. Further, by providing the light guide 5b around the hole 5a of the backlight unit 5, it is possible to further suppress the occurrence of illuminance unevenness in the region corresponding to the hole 5a of the liquid crystal display unit 3.

Further, by using a Fresnel lens as the lens 4a of the camera unit 4, the depth of the camera built-in display unit 1 can be further reduced.
Furthermore, since only the shutter area 6 is controlled to blink, the user is hardly aware of the flicker of the liquid crystal display unit 3.

As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to above-described embodiment, If it is those skilled in the art which belongs to the technical field of this invention, various in the range which does not deviate from the meaning of this invention. Embodiments can be implemented.
For example, in the above-described embodiment, an example in which one camera unit 4 is provided has been described, but a configuration in which two or more sets of camera units 4, holes 5a, light guides 5b, and shutter regions 6 are provided may be employed. For example, by providing two camera units 4, stereo viewing can be performed using camera imaging data output from these camera units 4.

Further, by alternately complementing the images captured by the two camera units 4, it is possible to increase the number of frames per unit time of the complemented camera images while increasing the off display interval of each shutter region 6. it can.
Further, more camera units 4 are provided, and the camera unit 4 in the vicinity of an area where an application for performing a face-to-face call such as a videophone is executed is selected from the display area of the liquid crystal display unit 3 and used. You can also.
Therefore, the present invention is defined by the technical idea described in the claims.

The display device according to the present invention can be used as a display device for a mobile phone, a PDA (Personal Digital Assistant), a movie camera, etc., in addition to a display device for a general personal computer, a liquid crystal television, and the like.
For example, when the display device according to the present invention is applied to a liquid crystal television and an announcement document is displayed on the liquid crystal display unit 3 at a television station or the like, the line of sight of the announcer does not deviate from the camera, so that the viewer does not feel discomfort.

Further, the image captured by the camera unit 4 can be displayed on the liquid crystal display unit 3 as it is to be used as a mirror, or applied to a photo booth (registered trademark). In addition, the liquid crystal display unit 3 can be used as photographing illumination for the camera unit 4 by displaying white (displaying the entire screen off) or as a surveillance camera by being applied to an operation panel of an ATM (Automated Teller Machine). .
Further, the camera unit 4 can be separably disposed on the back of the liquid crystal display unit 3 without being incorporated in the display device.

It is drawing which shows the structure of a display apparatus with a built-in camera, Comprising: (a) is a front view of a display apparatus with a built-in camera, (b) is a fragmentary sectional view of a display apparatus with a built-in camera. It is a block block diagram of a control circuit. It is a flowchart explaining operation | movement of a control circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camera built-in display apparatus 2 Case 3 Liquid crystal display part 4 Backlight unit 5 Camera unit 5a Hole 5b Light guide 6 Shutter area 10 Shutter control part 11 Aperture data switching part 12 Camera control part

Claims (5)

A liquid crystal display that includes a transmissive liquid crystal panel and displays input image data;
A backlight unit disposed on the back side of the liquid crystal display unit;
A camera unit disposed on the back side of the backlight unit;
A hole formed in the backlight unit in accordance with the position of the lens of the camera unit;
Based on image data input from the outside, the display of the area near the hole is turned off display through which light from the front side is transmitted, and is generated every predetermined time and output to the liquid crystal display unit, A shutter control unit that outputs image data input from the outside to the liquid crystal display unit as it is outside the predetermined time;
A display device comprising: The hole extends in a tapered shape toward the front side;
The display device according to claim 1. Using a Fresnel lens for the lens of the camera unit,
The display device according to claim 1, wherein the display device is a display device. A plurality of the camera unit and the hole;
The shutter control unit has a configuration for performing shutter control for the plurality of cameras;
The display device according to claim 1, wherein the display device is a display device. A liquid crystal display unit including a transmissive liquid crystal panel, a backlight unit disposed on the back side of the liquid crystal display unit, a camera unit disposed on the back side of the backlight unit, and a lens position of the camera unit In addition, there is provided a control method for a display device comprising: a hole formed in the backlight unit; and a shutter control unit that generates image data in which a display of a region near the hole is turned off to transmit light from the front side. There,
The shutter control unit generates image data at predetermined time intervals based on image data input from the outside to generate image data in which the display of the area near the hole is turned off to transmit light from the front side. Output to
Outside the predetermined time, image data input from the outside is directly output to the liquid crystal display unit,
A control method for a display device.

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