JP2013182095A - Multiple screen display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multiple screen display device capable of reducing differences in color characteristics in a plurality of image display devices.SOLUTION: A multiple screen display device includes: a plurality of image display devices 40 and 41; at least one of LED light sources 20 and 21; and a light guide section 30 for equally distributing and guiding fluxes emitted from the respective LED light sources 20 and 21. The respective image display devices 40 and 41 include: light tunnels 5a and 5b for receiving the flux distributed and guided by the light guide section 30; DMD elements 11a and 11b for carrying out optical modulation on the flux emitted from the light tunnels 5a and 5b on the basis of image information; and a projection optical system 12 for magnifying and projecting the flux with optical modulation carried out by the DMD elements 11a and 11b on a screen 13.

Description

  The present invention relates to a multi-screen display device including a plurality of image display devices.

  Various multi-screen display devices that realize a large screen by arranging a plurality of image display devices side by side have been proposed. In recent years, as a light source for a plurality of image display devices constituting a multi-screen display device, a solid light emitting element, particularly a light emitting diode (hereinafter referred to as “LED element”), instead of a conventionally used metal halide lamp and high pressure mercury lamp. It has been proposed to use

  By using an LED element as a light source, it is possible to reduce the size and power consumption of an image display device, and there are advantages such as a longer life than a conventional metal halide lamp and high-pressure mercury lamp, In order to secure a sufficient amount of light with a small amount of light emission, a configuration is considered in which a plurality of LED elements are arranged in an array as described in Patent Document 1. In addition, a configuration in which a plurality of LED elements are arranged so as to have an aspect ratio substantially equal to the aspect ratio of a reflective light modulation element that modulates light emitted from a light source based on image information is becoming mainstream.

Japanese Patent No. 3585097

  However, in the multi-screen display device equipped with the LED light source as described above, a plurality of screens constituting the multi-screen display device are affected by the emission spectral characteristics of each LED element (red, green, blue) and the manufacturing tolerance of the peak wavelength. Since the color characteristics of the light beam projected on the screen are different between the image display devices, it is necessary to perform color matching between the plurality of image display devices, but these color matching is difficult.

  Therefore, an object of the present invention is to provide a multi-screen display device that can reduce the difference in color characteristics among a plurality of image display devices.

  A multi-screen display device according to the present invention is a multi-screen display device including a plurality of image display devices, and is a guide that uniformly distributes and guides at least one LED light source and a light beam emitted from each LED light source. Each image display device includes a first integrator element that receives the light beam distributed and guided by the light guide unit, and the light beam emitted from the first integrator element as image information. A reflection-type light modulation element that performs light modulation on the basis of the reflection-type light modulation element; and a projection optical system that enlarges and projects the light beam modulated by the reflection-type light modulation element onto a screen.

  According to the present invention, since the light beam emitted from at least one LED element is evenly distributed and guided by the light guide unit, the first integrator element of each image display device is guided from the light guide unit. The light beam can be received evenly. For this reason, the color characteristics of the light beams enlarged and projected on the screen in each image display apparatus are substantially the same, and the difference in color characteristics among the plurality of image display apparatuses constituting the multi-screen display apparatus can be reduced.

1 is a configuration diagram of a multi-screen display device according to Embodiment 1. FIG. It is a timing chart explaining LED drive by a signal processing part. 6 is a configuration diagram of a multi-screen display device according to Embodiment 2. FIG. It is a block diagram of the LED light source device which concerns on a modification.

<Embodiment 1>
Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a multi-screen display device according to Embodiment 1 of the present invention. As shown in FIG. 1, the multi-screen display device includes at least one (for example, two) LED light source devices 20 and 21 that are LED light sources and a plurality (for example, four) optical fibers 31 that are light guides 30. To 34, and a plurality of (for example, two) image display devices 40 and 41.

  The LED light source devices 20 and 21 include an LED element 1R that emits red (R) light, an LED element 1G that emits green (G) light, an LED element 1B that emits blue (B) light, and three collimator lens groups. 2R, 2G, 2B, a dichroic mirror group 3, a condenser lens group 4, and an LED drive circuit 6 are provided.

  LED elements 1R, IG, and 1B each emit substantially radial light. The collimator lens groups 2R, 2G, and 2B are provided so as to correspond to the LED elements 1R, 1G, and 1B, respectively, and collimate the light emitted from the LED elements 1R, 1G, and 1B and emit it toward the dichroic mirror group 3. To do. The dichroic mirror group 3 combines the light emitted from the collimator lens groups 2R, 2G, and 2B as parallel light on the same optical axis and emits the light toward the condenser lens group 4.

  The condenser lens group 4 condenses the parallel light emitted from the dichroic mirror group 3 on the imaging surfaces 14a and 14b which are the focal point of the condenser lens group 4 and imaged in a certain area. Here, the imaging surface 14a is a focal point where the condenser lens group 4 of the LED light source device 20 condenses, and the imaging surface 14b is a focal point where the condenser lens group 4 of the LED light source device 21 condenses.

  The optical fibers 31 to 34 equally distribute and guide the light beams emitted from the respective condenser lens groups 4 of the LED light source devices 20 and 21. The optical fibers 31 and 32 are arranged so that the incident surfaces thereof are located on the imaging surface 14a, and the optical fibers 33 and 34 are arranged so that the incident surfaces thereof are located on the imaging surface 14b.

  Next, the image display devices 40 and 41 will be described. The image display device 40 includes a light tunnel 5a (first integrator element), a relay lens group 9, a TIR prism 10, a DMD element 11 (reflection type light modulation element), a DMD driving circuit 15a, and a signal processing unit 17a. A projection optical system 12 and a screen 13. The image display device 41 includes a light tunnel 5b (first integrator element), a relay lens group 9, a TIR prism 10, a DMD element 11, a DMD driving circuit 15b, a signal processing unit 17b, and a projection optical system 12. And a screen 13. The image display device 41 has the same configuration as that of the image display device 40. However, for convenience of explanation, the light tunnel 5b, the DMD drive circuit 15b, and the signal processing unit 17b are denoted by reference numerals different from those of the image display device 40. To do.

  The light tunnels 5a and 5b receive light beams distributed by the optical fibers 31 to 34. More specifically, the emission side end portions of the optical fibers 31 and 33 are connected to the incident side end portion of the light tunnel 5a, and the light tunnel 5a transmits the light flux supplied from the optical fibers 31 and 33 to the light tunnel 5a. It integrates by repeating reflection inside and synthesizes by making the luminance distribution uniform. The light-emitting end portions of the optical fibers 32 and 34 are connected to the light-incident end portion of the light tunnel 5b. The light tunnel 5b reflects the light flux supplied from the optical fibers 32 and 34 inside the light tunnel 5b. It integrates by repeating and synthesize | combines by making luminance distribution uniform.

  The relay lens group 9 collimates the light beams emitted from the light tunnels 5a and 5b and emits them to the TIR prism 10. The TIR prism 10 reflects the light beam emitted from the relay lens group 9 and emits it toward the DMD element 11, and passes the light beam emitted from the DMD element 11 as it is and emits it toward the projection optical system 12.

  The signal processing unit 17a controls the DMD driving circuit 15a and the LED driving circuit 6 of the LED light source devices 20 and 21. The signal processing unit 17a outputs a synchronization signal for controlling the DMD driving circuit 15b to the signal processing unit 17b. The signal processing unit 17b controls the DMD driving circuit 15b based on the synchronization signal output from the signal processing unit 17a. The DMD driving circuits 15a and 15b drive the DMD elements 11 based on the synchronization signals output from the signal processing units 17a and 17b, respectively. The DMD element 11 modulates light based on R, G, B video data (image information) input from the outside, and emits the light to the projection optical system 12 via the TIR prism 10. The projection optical system 12 enlarges and projects the light beam emitted from the TIR prism 10 onto the screen 13.

  Next, control of the DMD drive circuits 15a and 15b and the LED drive circuit 6 by the signal processing units 17a and 17b will be described with reference to FIGS. FIG. 2 is a timing chart for explaining LED driving by the signal processing unit 17a. The signal processing unit 17a controls the LED driving circuit 6 so that each LED of the LED light source devices 20 and 21 emits light in a time division manner. The signal processing units 17 a and 17 b cause the DMD element 11 to optically modulate the light flux emitted from the LED light source devices 20 and 21, and project the light-modulated light flux on the screen 13. Thus, since the light beams emitted from the two LED light source devices 20 and 21 are respectively distributed to the two image display devices 40 and 41, the LED light emission timings of the two LED light source devices 20 and 21 are distributed. Need to be synchronized.

  The signal processing unit 17a of the image display device 40 is MASTER, and the signal processing unit 17b of the image display device 41 is SLAVE. The signal processing unit 17a on the MASTER side controls the DMD driving circuit 15a on the basis of the synchronization signal generated by the signal processing unit 17a and R, G, B video data input from the outside, and at the same time in the LED light source device 20 The LED driving circuit 6 and the LED driving circuit 6 in the LED light source device 21 are controlled.

  On the other hand, the signal processing unit 17b on the SLAVE side controls the DMD drive circuit 15b at the same timing as that on the MASTER side based on the synchronization signal generated by the signal processing unit 17a on the MASTER side. The LED light emission timings of the devices 20 and 21 and the DMD drive timings of the two image display devices 40 and 41 are synchronized. In FIG. 2, the number of times each LED emits light is four times within the period of the synchronization signal, but the number of times each LED emits light may be controlled to an arbitrary number.

  When the number of LED light source devices is m and the number of image display devices is n, all LED light source devices (second to m-th units) are controlled by information from a signal processing unit (MASTER). In the signal processing unit, the signal processing unit of the first image display device is MASTER, and the signal processing units of the second to n-th image display devices are SLAVE.

  Next, the operation of the multi-screen display device will be described. The light beam condensed on the imaging surface 14 a in the LED light source device 20 is distributed by the optical fibers 31 and 32, and the light beam condensed on the imaging surface 14 b in the LED light source device 21 is distributed by the optical fibers 33 and 34. Is done.

  The light beams distributed by the optical fibers 31 and 33 are evenly distributed on the incident surface of the light tunnel 5a of the image display device 40, and the light beams distributed by the optical fibers 32 and 34 are evenly distributed on the incident surface of the light tunnel 5b of the image display device 41. Is incident on. Then, the light beam modulated by the DMD element 11 is enlarged and projected on the screen 13 via the projection optical system 12 via the relay lens group 9 and the TIR prism 10 from the exit surfaces of the light tunnels 5a and 5b. .

  In the multi-screen display device, the light beams emitted from the two LED light source devices 20, 21 have different color characteristics and luminance characteristics due to the manufacturing tolerances of the LED elements 1R, 1G, 1B and the manufacturing tolerance of the dichroic mirror group 3. However, by guiding them equally to the incident surfaces of the light tunnels 5a and 5b of the two image display devices 40 and 41, the color characteristics and luminance characteristics of the light beams projected from the two image display devices 40 and 41 are as follows. It becomes almost the same.

  In addition, with regard to lamps that have been used as light sources, an image display device having a lamp changer function as a redundancy function for automatically switching from a failed lamp to a new lamp is used in case of a lamp failure. There is a multi-screen display device. This function is effective as a means to prevent the loss of video, but after the lamp has been switched to a new lamp, the brightness and hue between the image display apparatus switched to the new lamp and other image display apparatuses. Therefore, it is necessary to perform brightness matching and color matching again.

  In the multi-screen display device according to the first embodiment, the luminous flux from the LED light source devices 20, 21 is evenly distributed to the image display devices 40, 41. Therefore, when one LED light source device fails, the image is displayed. There is also an effect that only the brightness of the display devices 40 and 41 is lowered, and it is unnecessary to readjust the screen loss, brightness matching, and color matching.

  As described above, in the multi-screen display device according to the first embodiment, since the light beams emitted from the LED light source devices 20 and 21 are evenly distributed and guided by the light guide unit 30, each image display device 40, Forty-one light tunnels 5a and 5b can receive the light flux evenly. For this reason, the color characteristics of the light beams enlarged and projected on the screen 13 in each of the image display devices 40 and 41 are substantially the same, and the difference in color characteristics between the two image display devices 40 and 41 constituting the multi-screen display device. Can be reduced. Further, since the luminance characteristics of the light beams are substantially the same, the difference in luminance between the two image display devices 40 and 41 can be reduced.

  Further, the light guide unit 30 uniformly guides the light beams emitted and distributed from the LED light source devices 20 and 21 to the light tunnels 5a and 5b of the image display devices 40 and 41. 21, the light tunnels 5a and 5b of the image display devices 40 and 41 can receive the light flux evenly. As a result, the light output can be improved, and the color characteristics and luminance characteristics between the two image display devices 40 and 41 can also be reduced.

  In the present invention, the luminous fluxes emitted from the plurality of LED light source devices 20 and 21 are evenly distributed to the corresponding plurality of image display devices 40 and 41, so that the LED elements 1R, 1G, 1B and It is devised so that the influence of variations in the color characteristics and luminance characteristics of the light flux caused by the dichroic mirror group 3 does not occur between the plurality of image display devices 40 and 41. For example, in the case of an image display device in which three liquid crystal panels (red, green, and blue) are mounted as light modulation elements, red, green, and blue are separated into three colors by a dichroic mirror inside the image display device. Therefore, even if the light beam emitted from the LED light source device is evenly distributed to a plurality of image display devices, variations occur again in the image display device. For this reason, in order to reduce the difference in color characteristics among a plurality of image display devices, it can be said that a DMD element that does not need to be separated into three colors of red, green, and blue is suitable as the light modulation element.

<Embodiment 2>
FIG. 3 is a configuration diagram of the multi-screen display device according to the second embodiment. The multi-screen display device according to the second embodiment is a light that is a second integrator element arranged so that the incident surfaces are positioned on the imaging surfaces 14 a and 14 b of the condenser lens groups 4 in the LED light source devices 20 and 21. Tunnels 18a and 18b are provided. 3, the same reference numerals as those in FIG. 1 denote the same or corresponding parts as those in the first embodiment, and a description thereof will be omitted.

  The light tunnel 18a is disposed so that the incident surface of the light tunnel 18a is positioned on the imaging surface 14a of the condenser lens group 4 of the LED light source device 20, and the incident side end portions of the optical fibers 31 and 32 are emitted from the light tunnel 18a. Connected to the side edge. The light tunnel 18b is disposed so that the incident surface of the light tunnel 18b is positioned on the imaging surface 14b of the condenser lens group 4 of the LED light source device 21, and the incident side end portions of the optical fibers 33 and 34 are emitted from the light tunnel 18b. Connected to the side edge. The exit end portions of the optical fibers 31 and 33 are connected to the entrance end portion of the light tunnel 5a, and the exit end portions of the optical fibers 32 and 34 are connected to the entrance end portion of the light tunnel 5b. Thus, the optical fibers 31 to 34 guide the light beams emitted from the light tunnels 18a and 18b evenly to the light tunnels 5a and 5b.

  As described above, in the multi-screen display device according to the second embodiment, when the light beams collected on the imaging surfaces 14a and 14b are distributed by the optical fibers 31 to 34, the incident surface of the light tunnel 18a is the imaging surface. The light tunnel 18a is disposed so as to be positioned at 14a, and the light tunnel 18b is disposed so that the incident surface of the light tunnel 18b is positioned at the imaging surface 14b, so that the light beams emitted from the exit surfaces of the light tunnels 18a and 18b Are evenly distributed by the optical fibers 31 to 34.

  Since the light tunnels 18a and 18b receive the light beams collected on the imaging surfaces 14a and 14b, the accuracy of receiving the light beams can be improved. Therefore, two image display devices can be used as compared with the first embodiment. Luminance and chromaticity uniformity of the luminous flux between 40 and 41 are improved. For this reason, it is possible to further improve the identity of the color characteristics and luminance characteristics of the light beams projected from the two image display devices 40 and 41 constituting the multi-screen display device.

<Modification of Embodiments 1 and 2>
In the first and second embodiments described above, the sequential mirror method shown in FIG. 4 may be adopted as a method for synthesizing the light emitted from the LED elements 1R, 1G, and 1B. Hereinafter, the contents of photosynthesis by the sequential mirror method will be described with reference to FIG.

  In the sequential mirror system, a red reflecting dichroic mirror 50 and a blue reflecting dichroic mirror 51 are arranged instead of the dichroic mirror group 3. The green light emitted from the LED element 1G is collimated by the corresponding collimator lens group 2G, passes through the blue reflecting dichroic mirror 51 and the red reflecting dichroic mirror 50, and is emitted toward the condenser lens group 4.

  The blue light emitted from the LED element 1B is collimated by the corresponding collimator lens group 2B, reflected by the blue reflecting dichroic mirror 51, transmitted through the red reflecting dichroic mirror 50, and emitted toward the condenser lens group 4. The The red light emitted from the LED element 1R is collimated by the corresponding collimator lens group 2R, reflected by the red reflection dichroic mirror 50, and emitted toward the condenser lens group 4.

  As described above, red light, green light, and blue light are combined as parallel light on the same optical axis by the red reflection dichroic mirror 50 and the blue reflection dichroic mirror 51 and emitted to the condenser lens group 4. In this case, the same effect as in the first and second embodiments can be obtained.

  In the first and second embodiments, a multi-screen display device including two LED light source devices 20 and 21 and two image display devices 40 and 41 is described as an example. The combination of display devices (when the number of LED light sources is m and the number of image display devices is n) is m = n, m> n, m <n (m is an integer of 1 or more, n is 2) (Integer above) can also be supported. However, when the number of LED light sources is larger than the number of image display devices (when m> n), the brightness is not improved by the increase in the number of LED light source devices due to the etendue principle.

  Although the optical fiber length is related to the selection of the material of the optical fiber, it is more efficient to adopt an optical fiber having a fiber length as short as possible as a means for suppressing light loss inside the optical fiber.

In addition, regarding the NA specification (numerical aperture) of the optical fiber, it is more efficient to select it after considering the matching with the optical system to be combined because the optical loss can be suppressed. For example, when the light flux from the LED element is combined with an optical fiber corresponding to the light tunnel entrance surface, the angle at which the light flux from the LED element is condensed is represented by Fno.
When Fno = 1.0: Fiber specification: NA = about 0.5
In the case of Fno = 2.5 Fiber specification: NA = approximately 0.2
It becomes.

  The light beam condensed on the imaging surface usually has a certain area or more (for example, in the case of the 0.9 inch class DMD element 11, the imaging area of about 9 mm × about 6 mm). ) In order to propagate the collected light flux to the entrance surface of the light tunnel, it is propagated by an optical fiber bundle (hereinafter referred to as a bundle fiber) in which a plurality of optical fibers are bundled corresponding to the area of the imaging surface in order to improve efficiency. Is efficient.

  As the specification of the bundle fiber in this case, considering the bundle fiber routing and the loss at the time of the bundle, a product having a diameter of one optical fiber of several microns to several hundred microns is selected. If the dimension excluding the thickness of the sleeve required as the outermost peripheral guide when bundling is made the same dimension as the shape of the imaging plane or the light tunnel, light can be propagated more efficiently.

  Moreover, although the optical fiber was employ | adopted as a light guide part, you may employ | adopt not only an optical fiber but the member which can guide light as a light guide part.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

  5a, 5b Light tunnel, 11a, 11b DMD element, 13 screen, 18a, 18b Light tunnel, 20, 21 LED light source device, 30 Light guide unit, 40, 41 Image display device.

Claims (3)

A multi-screen display device comprising a plurality of image display devices,
At least one LED light source;
A light guide that uniformly distributes and guides the luminous flux emitted from each of the LED light sources,
Each of the image display devices
A first integrator element that receives the luminous flux distributed and guided by the light guide;
A reflective light modulation element that modulates the light flux emitted from the first integrator element based on image information;
A multi-screen display device comprising: a projection optical system that enlarges and projects the light beam modulated by the reflective light modulation element onto a screen. A plurality of the LED light sources,
2. The multi-screen display device according to claim 1, wherein the light guide unit uniformly guides light beams emitted and distributed from the LED light sources to the first integrator elements of the image display devices. A second integrator element disposed on the imaging surface of the LED light source so that the incident surface is located;
The multi-screen display device according to claim 1, wherein the light guide unit uniformly guides the light beam emitted from the second integrator element to the first integrator element of each of the image display devices.

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