JP2007206488A - Projection type display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the luminance of a man region by more surely discriminating the man region within a projection range. <P>SOLUTION: A sensor section 12 is equipped with, for example, thermopile sensors of 16×16 elements. Each thermopile sensor detects the IR rays from 256 regions of a partitioned screen S and outputs a detection signal. A controller 13 acquires a plurality of the detection signals, binarizes the same, and discriminates the man region existing in the projection range of the screen 3 based on the binarization data. The controller 13 supplies the information on the discriminated man region to an image processing section 14. The image processing section 14 generates the corrected image reduced to the extent of not dazzling the luminance of the man region. A projection section 11 projects the corrected image to the screen S. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a projection display device.

  Conventionally, a projection display device such as a liquid crystal projector that projects an image on a screen is known. In addition, as a projection type display device, there is also a type in which a region of a presenter standing in front of a screen is determined, and a dimming process is performed to reduce the light in this region so that the eyes of the presenter are not dazzled (for example, Patent Document 1).

FIG. 8 shows such a projection display device. The projection type display device 51 uses a CCD camera to determine the region of the presenter 52 standing in front of the screen Sc. Then, the projection display device 51 generates a corrected image in which the luminance of the determined area is reduced, and projects the corrected image on the screen Sc.
JP 2000-305481 A (page 3-4, FIGS. 1 and 2)

  However, in the conventional projection display device, a CCD camera is used to determine the region of the presenter 52. Therefore, a person cannot be determined unless it is brightened by illumination or projection light.

  Further, if the brightness of the human area is the same as that of the screen Sc, the human area cannot be determined. Furthermore, when a CCD camera is used, data processing becomes complicated and the system itself becomes expensive.

The present invention has been made in view of such conventional problems, and provides a projection display device that can more reliably determine a human area within a projection range and reduce light in the human area. The purpose is to provide.
Another object of the present invention is to provide a projection display device that can reduce the cost of the system.

In order to achieve this object, a projection display device according to the first aspect of the present invention provides:
A plurality of infrared sensors that detect infrared rays within a projection range of the image and output a detection signal having a signal level corresponding to the detected amount of infrared rays;
A human region discriminating unit for discriminating a human region existing in the projection range based on the detection signal output by each infrared sensor;
An image processing unit that generates a corrected image in which the luminance of the human region determined by the human region determination unit is reduced with respect to the original image;
And an image projection unit that projects the corrected image generated by the image processing unit into the projection range.

  The plurality of infrared sensors are provided corresponding to divided areas set by dividing the projection range, and each infrared sensor detects infrared rays from the person for each divided area, The detection signal may be output.

  The human region determining unit may binarize the signal levels of the detection signals output from the plurality of infrared sensors and determine the human region based on the binarized data.

  According to the present invention, it is possible to more reliably determine a human area within the projection range and reduce the light in this human area. In addition, the system can be made inexpensive.

Hereinafter, a projection display apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows the configuration of a projection display device according to this embodiment.
The projection display device 1 according to the present embodiment includes a projection unit 11, a sensor unit 12, a control unit 13, and an image processing unit 14.

  The projection unit 11 projects the image supplied from the control unit 13 within the projection range of the screen S.

  The sensor unit 12 includes a thermopile sensor as a plurality of infrared sensors. The thermopile sensor outputs a detection signal having a signal level corresponding to the temperature difference between the hot junction and the cold junction using the Seebeck effect.

  FIG. 2 is a diagram illustrating an example of the thermopile sensor 21, and is a front view of the thermopile sensor 21 viewed from the front with the person side as a viewpoint. As shown in FIG. 2, the thermopile sensor 21 has four hot junction parts 21a and four cold junction parts 21b.

  Each hot junction part 21a and each cold junction part 21b are formed on a semiconductor substrate, and each hot junction part 21a and each cold junction part 21b are n-type polysilicons 21c and p which are different kinds of conductors, respectively. It is connected to the type polysilicon 21d.

  The four hot contact portions 21a are covered with an infrared absorption film 21e, and the infrared absorption film 21e absorbs infrared rays from a person and converts them into thermal energy, and supplies the thermal energy to each hot contact portion 21a.

  A space (not shown) for holding the temperature of each warm contact portion 21a is formed under each warm contact portion 21a, and the four openings 21f are connected to this space portion. And the thermopile sensor 21 outputs the detection signal of the signal level corresponding to the temperature difference of each warm junction part 21a and each cold junction 21b from terminal 21g, 21h. The signal level of this detection signal corresponds to the amount of detected infrared light.

  The sensor unit 12 includes such a thermopile sensor 21, for example, only 16 × 16 elements. As shown in FIG. 3, the projection range 31 of the screen S is divided into 16 × 16 vertical and horizontal, and divided areas (i, j) (i = 0-15, j = 0-15) are set, respectively. The 16 × 16 element thermopile sensor 21 (i, j) is provided to correspond to each of the divided regions.

  The control unit 13 illustrated in FIG. 1 includes a CPU, a ROM, a RAM, an A / D converter, and the like (not shown), and controls the projection display device 1 as a whole.

  Specifically, the control unit 13 discriminates a human region and controls each unit so that an image in which the luminance of this region is reduced is projected into the projection range 31. For this reason, the control unit 13 instructs the sensor unit 12 so that each thermopile sensor 21 detects infrared rays from a person. And the control part 13 acquires each detection signal from the sensor part 12, performs A / D conversion, and converts it into the detection signal as digital data.

  The control unit 13 binarizes the detection signal by comparing each detection signal with a preset threshold value. The ROM provided in the control unit 13 stores this threshold value.

  For example, it is assumed that the signal level of the detection signal has 10 levels, and this detection signal has a value as shown in FIG. Further, it is assumed that the threshold is set to “5”.

  In the case of the thermopile sensor 21 (0,0), the control unit 13 compares the signal level “0” of the detection signal of the thermopile sensor 21 (0,0) with the threshold value “5”, and binarizes the signal. The level is “0”. The signal level “0” indicates that the corresponding thermopile sensor 21 did not detect infrared rays from a person.

  In the case of the thermopile sensor 21 (1, 1), the control unit 13 compares the signal level “5” of the detection signal of the thermopile sensor 21 (1, 1) with the threshold value “5”, and binarizes the signal. The level is “1”. The signal level “1” indicates that the corresponding thermopile sensor 21 has detected infrared rays from a person. In this way, the control unit 13 discriminates the human region 33 existing in the projection range 31 as shown in FIG.

  The control unit 13 supplies information on the human region 33 to the image processing unit 14 and instructs to generate a corrected image in which the luminance of the human region 33 is reduced. When the corrected image data is supplied from the image processing unit 14, the control unit 13 supplies the corrected image data to the projecting unit 11 and projects the corrected image onto the projecting unit 11. The unit 11 is controlled.

  The image processing unit 14 is supplied with original image data from the outside and performs image processing on the original image data. The image processing unit 14 is supplied with the information on the human region 33 from the control unit 13 and is instructed to correct the original image data supplied from the outside to reduce the luminance in the human region 33 to the extent that it is not dazzling as image processing. To generate a corrected image.

Next, the operation of the projection display device 1 according to this embodiment will be described.
The projection display device 1 executes the projection control process according to the flowchart shown in FIG.

  That is, the control unit 13 instructs the sensor unit 12 to detect infrared rays, and acquires the detection signal output from each thermopile sensor 21 from the sensor unit 12 (step S11).

  The control unit 13 performs A / D conversion on the signal level of the detection signal (step S12).

  The control unit 13 binarizes each detection signal by comparing the signal level of each detection signal subjected to A / D conversion with a threshold value (step S13).

  The controller 13 determines the human area 33 based on the binarized data (step S14).

  The control unit 13 supplies the determined information of the human region 33 to the image processing unit 14 and instructs the image processing unit 14 to generate a corrected image (step S15).

  The image processing unit 14 generates a corrected image in which the luminance of the human area 33 is reduced to such an extent that it is not dazzling, and supplies the corrected image data to the control unit 13 (step S16).

  The control unit 13 supplies the correction image data supplied from the image processing unit 14 to the projection unit 11 and controls the projection image 31 to project the correction image (step S17).

Next, a specific operation of the projection display device 1 will be described.
When the projection unit 11 projects an uncorrected image on the screen S, an image as shown in FIG. 6A is projected in the projection range 31 of the screen S. In this case, each thermopile sensor 21 of the sensor unit 12 detects infrared rays from the person 2 as shown in FIG. 6B and outputs detection signals having signal levels corresponding to the amount of infrared rays.

  The control unit 13 acquires this detection signal from the sensor unit 12, performs A / D conversion, and binarizes it. The control unit 13 determines a human region 33 as shown in FIG. 6C based on the binarized image. The control unit 13 supplies the information on the human area to the image processing unit 14. Based on this information, the image processing unit 14 generates a corrected image P as shown in FIG. 7A and supplies the corrected image P to the control unit 13.

  When the data of the correction image P is supplied from the control unit 13, the projection unit 11 projects the correction image P into the projection range 31. When the projection unit 11 projects the corrected image P into the projection range 31, an image in which the luminance of the human area 33 is reduced is displayed on the screen S as shown in FIG.

  As described above, according to the present embodiment, the projection display apparatus 1 includes the plurality of thermopile sensors 21 in the sensor unit 12, detects infrared rays from the person 2 within the projection range 31, and uses this detection signal. Based on this, the human region 33 in each projection range 31 is discriminated, and a corrected image in which the luminance in the human region 33 is reduced is generated.

  Accordingly, the person 2 can be reliably discriminated even in a dark place, and it is not necessary to brighten the illumination area or the projection light in order to discriminate the person area 33. Even if the brightness of the human area 33 is the same as that of the screen S, the human area 33 can be more reliably determined. Also, data processing is simple and the system is inexpensive.

It is a block diagram which shows the structure of the projection type display apparatus which concerns on embodiment of this invention. It is a front view which shows the structure of the thermopile sensor in the sensor part shown in FIG. It is a figure which shows a response | compatibility with a some thermopile sensor and the division area of the projection range of a screen. It is a figure which shows the process of the detection signal which each thermopile sensor of a sensor part shown in FIG. 1 outputs, (a) shows the signal level of the detection signal which each thermopile sensor outputs, (b) shows a detection signal. The binarized temperature data is shown. It is a flowchart which shows the projection control process which the control part shown in FIG. 1 performs. It is a figure which shows the operation | movement (the 1) of the projection type display apparatus which concerns on this embodiment, (a) shows the screen when not performing a light reduction process, (b) is the person area | region which the sensor part acquired. (C) is a figure which shows a person and a person area | region. It is a figure which shows operation | movement (the 2) of the projection type display apparatus which concerns on this embodiment, (a) shows the produced | generated correction image, (b) is a figure which shows the screen at the time of projecting a correction image. It is. It is a figure which shows the conventional projection type display apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Projection part 12 Sensor part 13 Control part 14 Image processing part 21 Thermopile sensor

Claims (3)

A plurality of infrared sensors that detect infrared rays within a projection range of the image and output a detection signal having a signal level corresponding to the detected amount of infrared rays;
A human region discriminating unit that discriminates a human region existing in the projection range based on the detection signal output by each infrared sensor;
An image processing unit that generates a corrected image in which the luminance of the human region determined by the human region determination unit is reduced with respect to the original image;
An image projection unit that projects the corrected image generated by the image processing unit within the projection range,
A projection type display device characterized by that. The plurality of infrared sensors are provided corresponding to divided areas set by dividing the projection range, and each infrared sensor detects infrared rays from the person for each divided area, Outputting the detection signal;
The projection display device according to claim 1. The human area determination unit binarizes a detection signal output from the plurality of infrared sensors, and determines the human area based on the binarized data.
The projection display device according to claim 1, wherein the projection type display device is a projection type display device.

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