JPH01149087A - Projection display and display device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method and a display device for projecting and displaying an image using a plurality of liquid crystal light valves, and more specifically relates to a full-color image and an independent display method. The present invention relates to a method and apparatus for projecting and displaying both monochrome and color images.

[Summary of the Disclosure] This specification and drawings describe a method and a display device for projecting and displaying an image using a plurality of liquid crystal light valves, in which a first plurality of image information is generated in a projection optical system using a liquid crystal light valve. At the same time, by making it possible to realize a second plurality of independent image information in the projection optical system within the same optical system using a second liquid crystal light valve, a plurality of different image information, More specifically, the present invention discloses a technique for projecting video images, graphic images, single character images, etc. alternately or by overlapping parts or all of them.

[Prior Art] In various presentations such as academic lectures and product announcements, when video images are projected and displayed to explain the images, call attention to them, or add other additional information, conventionally, It was common to stand in front of a projection display screen and support the relevant location with a pointer.

Alternatively, if it is possible to edit or process the video image in advance, characters or symbols may be added to the video image, or the color of a portion of the image may be changed.

[Problems to be solved by the invention] However, in this case, in order to save the original video, it is necessary to save both the original video and the edited video.
It was uneconomical. In addition, with video that has been edited and processed in this way, it is not possible to respond in accordance with the situation on the spot.
Videos shot or transmitted at a presentation cannot be edited or processed, and as a result, additional information cannot be added.

The present invention was discovered as a result of a search to eliminate the above-mentioned drawbacks of display methods and devices based on the prior art.

That is, an object of the present invention is to provide a method and a display device for displaying two sets of mutually independent video information using a simpler mechanism than those of the prior art. In particular, it is an object of the present invention to provide a method and a display device for displaying high-brightness full-color video images and, independently, monochrome or color images, by means of a significantly simpler mechanism than in the prior art.

Another object of the present invention is to display video information from a wide variety of video sources by simply providing an additional mechanism without using multiple types of display devices. An object of the present invention is to provide a method and a display device.

Yet another object of the present invention is to provide a method and display device for displaying video information from multiple video sources on the same screen using a single display device.

Still another object of the present invention is to add other information to the input video information and display it, or to select a temporal or spatial part of the input video information or a part of various attributes such as color. The object of the present invention is to provide a method and a display device for performing the selective display by providing an additional mechanism or changing a part of the inherent mechanism.

Still another object of the present invention is to provide a display device that can be used in a variety of applications as described above, and that is lightweight, compact, inexpensive, and power-saving.

[Means for Solving the Problems] The present invention relates to a method and apparatus for projecting and displaying two sets of mutually independent plurality of video information, and in the method of the first invention, a plurality of liquid crystal light valves are used. This projection display method is characterized by using the following steps (A) to (F).

(A) A first plurality of video information that changes or does not change over time is inputted in a time-divided manner, and a second plurality of video information that is independent of this is inputted in a non-time-divided manner. Outputting the first and second plurality of video information as first and second irradiation lights in a field-sequential manner, respectively, and introducing the first and second irradiation lights into first and second liquid crystal light valves, respectively. two sets of writing steps independent of each other; (B) synchronizing a plurality of non-time-shared irradiation lights from a single or multiple light sources with the plurality of video information when the plurality of video information is time-shared; , otherwise without the need for synchronization.
The first and second irradiation lights are applied to the first and second liquid crystal lights, respectively, from a projection light source system that is selectively lit in a time-division manner, or synchronized with multiple light sources as described above, or selectively lit in a time-division manner without the need for synchronization. (C) Spatial modulation of the first and second irradiation lights from the projection light source system by the first and second irradiation lights from the writing process in the first and second liquid crystal light valves; (D) magnifying and projecting the first and second modulated light from the first and second liquid crystal light valves in the projection optical system; (E) projecting the projection light from the projection optical system; The process of receiving light and forming an image to display the desired projected image on a screen.

(F) A step of displaying the second modulated light by superimposing or alternately projecting the second modulated light with part or all of the first modulated light.

Further, in the device according to the second invention, in a projection display device using a liquid crystal light valve, the following (a) to (
A display device characterized by having the mechanism of d).

(a) A first plurality of video information that changes or does not change over time is input in a time-divided manner, or a second plurality of video information that is independent from this is inputted in a non-time-division manner; 2. Outputting the plurality of video information of the first and second plurality of images as first and second irradiation lights in a field-sequential manner, respectively, and introducing the first and second irradiation lights into first and second liquid crystal light valves, respectively. (b) Synchronize a plurality of non-time-divided irradiation lights from a single or multiple light sources with the plurality of video information if the plurality of video information is time-divided; In this case, a projection light source system that selects each time-divisionally without the need for synchronization, or synchronizes multiple light sources as described above, or lights each light source in a time-divisionally selective manner without the need for synchronization; (c) writing of the two sets described above; first and second liquid crystal light valves that spatially modulate first and second illumination lights from the single or plural projection light source systems, respectively, with the illumination light from the light source systems; (d) first and second illumination lights from the projection light source systems; guiding the first and second irradiation lights to the first and second liquid crystal light bulbs, respectively;
A projection optical system that magnifies and projects the first and second modulated lights from the first and second liquid crystal lights/ R, G divided in time
, B (hereinafter referred to as R for red, G for green, and B for blue) is image information for each color.

[Function] Hereinafter, the basic configuration of the present invention will be explained in more detail with reference to the drawings.

3 and 4 are schematic diagrams showing the configuration of the basic components of the display device of the present invention, and FIG.
FIG. 2 is a schematic diagram showing an example of a method of converting an input signal into a time-division video signal.

Below, we will first describe a method for projecting and displaying video images using Figures 3 and 5.
The configuration shown in FIG. 4 may be used instead of the configuration shown in the figure.

First, the input non-time-divided image signal 21 (-
) is shown as an example of an RGB signal, and is converted into a time-divided image signal 23 which is time-divided by the time division mechanism 1 . This time division mechanism 1 may be constructed using a known technique, for example, as shown in FIG.
The RGB signals are time-compressed for each time, and the time-compressed color signals 22 are R', G', and B' signals, and G', B are
'Both signals are delayed by 1/3 field and 2/3 field with respect to the R' signal, respectively, to produce the G", B" signals, and the R', G', and B# signals (this is used as the subfield signal ), the Booker signals M1 are distinguishable from each other.
．． M2. Line-sequential time-division video signal 23 with M3 attached.
Output as . On the other hand, the time division mechanism 1 issues a synchronization signal 24 to the time division color selection mechanism 5. This synchronization signal is most simply the mutually distinguishable marker signal M
ll M2. M3 is fine.

The time division video signal 23 output from the time division mechanism 1 is C
The time-division video signal 23 is input to the CRT 2.
Image information (subfield information) for each color that is time-divided according to the time is outputted as irradiation light 31 in a field-sequential manner.

In the case of this configuration, the signals input to the CRT 2 are line sequential as described above, and as described later, the liquid crystal light valve (hereinafter referred to as LCLV) 3 receives the irradiation light 31 from the CRT and outputs it to the LCLV. Although the incident light 34 is modulated, it is not necessary or possible to transmit the color attributes of the irradiated light 31, so it is sufficient to use a monochrome device as the CRT 2.

Furthermore, regarding the mechanism for horizontally and vertically deflecting the electron beam in the CRT 2, it goes without saying that the electron beam is deflected in 1/3 of the time required for normal field image display in accordance with the subfield information for each color. do not have. Correspondingly, the luminescence of the phosphor is also subfield (1/18
It is necessary to define the phosphor material so that it effectively decays within approximately 0 seconds).

In the above description, the field picture is used as a unit, but the same effect can be easily achieved even in a configuration where the frame picture is used as a unit. Further, the input signal may be an NTSC signal, in which case an appropriate circuit is provided in the time division mechanism l to directly output the time compressed signals R', G', B' or R', G. It is also possible to obtain ``, B''.

Irradiation light 31 from the CRT 2 is incident on the photoconductive layer (not shown) side of the LCLV 3 to which a bias voltage has been applied in advance. The conductivity of the photoconductive layer of the LCLV3 changes depending on the intensity of the irradiated light from the CRT 2, and the photoconductive layer of the LCLV3 changes accordingly.
The voltage applied to each part on both sides of the liquid crystal cell changes.

The optical properties of a liquid crystal cell change depending on the applied voltage, so in the above LCLV3, the optical properties of the liquid crystal cell will differ for each part, and the LC
LV incident light 34 is spatially modulated.

By providing a reflective layer (not shown) between the photoconductive layer and the liquid crystal cell, spatially modulated light, ie.

The LCLV output modulated light 35 is reflected toward the incident light side, and is emitted toward a polarization beam splitter (hereinafter referred to as PBS) 6, which will be described later. By the way, here, L
The configuration and operation of the CLV are limited to those essential to this configuration, and the LCLV of this configuration is different from the configuration and operation of the LCLV of the prior art.
This is not to suggest that the LCLV of this configuration is better than the prior art LCLV.
The feature is that the configuration can be used almost as is.

On the other hand, the white light 32 emitted from the xenon lamp 4 is
Bs 6 and only the S-polarized component is reflected. For example, the time-division color selection mechanism 5 that sequentially selects the three colors R2O and H in time-division by the time-division color selection mechanism 5 sequentially selects three color filters of R, G, and H, for example. A simple mechanism to introduce into the optical path, more specifically, a mechanism that rotates a disk in which n sets of the same color filters are sequentially arranged in the circumferential direction at H/n per second, but is not limited to this and is known in the art. color selection mechanism can be used.

For example, there is a mechanism that changes the transmittance of each color of R, G, and B by controlling the voltage applied to the piezoelectric PLZT, and a mechanism that changes the transmittance of each color of R, G, and B by laminating electrochromic materials that produce colors of R, G, and B perpendicularly to the optical path. However, a mechanism in which colors are selected by sequentially applying voltage can be considered, and other techniques can also be used. Furthermore, as a mechanism that has both the pre-action of a light source and a color selection mechanism, a mechanism that sequentially blinks three color lamps of R, G, and B, or a mechanism that sequentially shuts off lighting with a shutter is also effective.

Furthermore, a light emitting diode may be used as the light source for the three colors R, G, and B in the same mechanism.

The time-division selective light thus time-divided is incident as LCLV incident light 34 on the liquid crystal cell of the LCLV, the optical properties of which change spatially as the conductivity of the photoconductive layer changes. In order for this LCLV incident light 34 to be spatially modulated in the liquid crystal cell and emitted by one reflective layer, it is essential in this configuration that the polarization direction is changed. Suitable liquid crystal operating modes for use in this case are, for example, hybrid field effect liquid crystal cells and ferroelectric liquid crystal cells.

The modulated light 35 emitted from the LCLV in this manner has a p-polarized light component, passes through the PBS 6, and becomes PBS-transmitted light 41 containing only the p-polarized light component. This light is guided to the projection optical system 7 and irradiated onto the display screen 8 as projection light 42 to form an image. As the projection optical system 7, essentially the same optical system as disclosed or implemented in various projection display apparatuses can be widely used. The display screen 8 may also be used as is for normal use.

In the above description, the basic configuration of the present invention is an apparatus in which each mechanism up to the projection optical system 7 is incorporated.

On the other hand, FIG. 4 shows another basic configuration of the present invention, in which the zero line configuration is characterized in that the time-division color selection mechanism 5 is operated before passing through the PBS 6. The other mechanisms are similar to the configuration shown in FIG. 3, and the same reference numerals indicate equivalent parts.

Now, FIG. 1 and FIG. 2 are diagrams showing an embodiment of the present invention. The following will be explained based on these.

1 is a diagram showing an embodiment based on the basic configuration of FIG. 3. In this embodiment, a second CRT 2', LCLV 3' and a time A splitting mechanism 5' is provided to provide an S-polarized light component when spatially modulating the p-polarized light, and the S-polarized light component is
The second image is displayed by being reflected by the projection optical system 7 and reflected by the projection optical system 7. This makes it possible to use the p-polarized light component, which was not used in the basic configuration shown in FIG.
Now it is possible to project and display images.

In realizing this embodiment, since the time-division color selection mechanisms 5 and 5' can be independently controlled, the time-division compressed video signal 23 and the non-time-division video signal 21' are spatially modulated independently. It can be converted into colored lights 35 and 35'.

Therefore, even in the case of time-division mode in which time-division color selection does not end within the field frequency, if the video signal 21' is computer graphics or still images, full color or monochrome display is possible. .

On the other hand, in the embodiment shown in FIG. 2, it is generally difficult to simultaneously operate two liquid crystal light valve systems to produce an image of a desired color. Therefore, when the first LCLV is applied, colors are selected in the same manner as the second LCLV is applied in the manner shown in FIG. For example, if you want to superimpose a character at the bottom of the screen using a single color of R, G, or B (for example, R), set R' to the third subfield signal. If you change the order so that

[Example] Hereinafter, the present invention will be explained in more detail by referring to Examples, but the present invention is not limited thereto.

Example 1 Using the apparatus shown in FIG. 1, projection display of two types of images was realized by the following method.

A video signal captured by a television camera is converted into a time-division video signal 23 through a time-division mechanism 1, and this is transmitted to a high-brightness CRT.
I entered 2. The output light of the CRT was introduced from the side of the photoconductive layer made of CdS of LCLV3, which was provided in close contact with the face plate of the CRT. The same LCLV has 10
A bias voltage of KHz was applied.

On the other hand, the white light 32 generated from the tooow xenon lamp 4 was guided to the PBS 6, and the S-polarized component was reflected by the PBS for time-division selection, and then input from the liquid crystal layer side of the LCLV 3.

Separately, explanatory texts and graphic images that have been preprogrammed and stored in the computer are input to the CRT2', and the output light of the CRT is transferred to the CRT of the LC'LV3'.
It was introduced from the side of the photoconductive layer made of dS. Same LICLV3
A bias voltage of 10 kHz was applied to '. Same L
From the liquid crystal layer side of the CLV 3', the 0 time division color selection mechanism 5' introduces the p-component of the R, G, and 8 color lights that are transmitted through the PBS and time division color selected, and the 0 time division color selection mechanism 5' transmits the time division color selection mechanism 5' at a different period from that of the same mechanism 5. When time division was performed and adjustments were made so that white characters were displayed using LCLV3', the resolution was 6 lines/sts.
, contrast) 18:1 video with white text superimposed on it.

-"Example 2 Using the apparatus shown in FIG. 2, the video image signal 21 is input to the time division mechanism 1, and the color is selected as shown in FIG. 5 using the time division color selection mechanism 5. When character/graphic information from the computer is sequentially input to the video signal 21' and the time-division color selection mechanism 5 is operated at a different cycle than before, the video image signal 21 is cut off. Still images were displayed colorfully.

[Effects of the Invention] As explained in detail above, by using the projection display method and display device of the present invention, the following effects were obtained.

■Additional information could be added without reducing the brightness of the original image.

■ It has become possible to add additional information on the spot to the original video without having to perform editing work to add text information etc. in advance.

■ Additional information added to the original video can be prepared in advance independently of the original video, or can be created on the spot using an input device such as a tablet or touch panel, and can be added to the situation. It is now possible to add superimposition to the original video as needed.

■ Multiple images can be projected and displayed alternately without forcing the viewer to shift their line of sight, reducing viewer fatigue.

[Brief explanation of the drawing]

1 and 2 are schematic diagrams showing one embodiment of the display device of the present invention, FIGS. 3 and 4 are schematic diagrams showing the configuration of the basic components of the display device of the present invention, and FIG. 5 is a schematic diagram showing an example of a method of converting an input signal into a time-division video signal in the configurations of FIGS. 3 and 4. FIG. l: Time division mechanism for input signals. 2.2'...Cathode ray tube (CRT), 3.3'...Liquid crystal light valve (LCLV), 4...
・Xenon lamp, 5.5'...Time division color selection mechanism, 6...Polarizing beam splitter (PBS). 7... Projection optical system, 8... Display screen,
21, 21'... Image signal (field signal), 22
...Time-compressed color signal (subfield signal), 23, 23'...Time-division video signal, 24...Synchronization signal, 25...Additional image signal, 31...Irradiation light, 32 ...White light, 33...Time-division color selection light, 34.34'...LCLV incident light, 3
5, 35'-LCLV output modulated light, 41...PBS transmitted light, 42... Projection light, 81
~94...Liquid crystal cell, 95...Reflector.

Claims (15)

[Claims] (1) A projection display method for projecting and displaying a plurality of images using a plurality of liquid crystal light valves, characterized in that the following steps (A) to (F) are used. (A) A first plurality of video information that changes or does not change over time is inputted in a time-divided manner, and a second plurality of video information that is independent of this is inputted in a non-time-divided manner. Outputting the first and second plurality of video information as first and second irradiation lights in a field-sequential manner, respectively, and introducing the first and second irradiation lights into first and second liquid crystal light valves, respectively. (B) synchronizing a plurality of non-time-divided irradiation lights from a single or multiple light sources with the plurality of video information when the plurality of video information is time-divided; , otherwise, the first and second projection light source systems are selected in a time-division manner without the need for synchronization, or synchronize multiple light sources as described above, or are selectively turned on in a time-division manner, respectively, without the need for synchronization. (C) In the first and second liquid crystal light valves, the first and second irradiation lights from the writing process are used to introduce the irradiation light from the projection light source system into the first and second liquid crystal light valves, respectively. (D) enlarging and projecting the first and second modulated lights from the first and second liquid crystal light valves in the projection optical system; (E) receiving and imaging the projection light from the projection optical system to display a desired projected image on a screen; (F) converting the second modulated light into a part of the first modulated light or The process of projecting and displaying images on top of each other or alternately. (2) The projection display method according to claim 1, wherein the plurality of pieces of video information are color-separated video information. (3) The projection display method according to claim 1, wherein the plurality of irradiation lights are color-separated irradiation lights. (4) The projection display method according to claim 1, wherein the desired projected image is a full-color image. (5) The projection display method according to claim 1, wherein the first and second irradiation lights from the projection light source system are colored lights time-divided in the same order. (6) The projection display method according to claim 1, wherein the first and second irradiation lights from the projection light source system are colored lights that are time-divided in different orders. (7) The projection display method according to claim 1, wherein the first and second irradiation lights from the projection light source system are colored lights divided at different time intervals. (8) The projection display method according to claim 5, 6, or 7, wherein the time-divided colored lights are red, green, and blue. (9) A projection display device using a plurality of liquid crystal light valves, characterized by comprising the following mechanisms (a) to (d). (a) A first plurality of video information that changes or does not change over time is inputted in a time-sharing manner, or a second
input the plurality of video information without time-sharing, output the first and second plurality of video information as first and second irradiation light respectively in a field-sequential manner, and (b) two sets of writing light source systems that introduce light into first and second liquid crystal light valves, respectively; If it is, the multiple video information is synchronized; otherwise, the multiple light sources are selected in time division without the need for synchronization, or multiple light sources are synchronized as described above, or each time is selected without the need for synchronization. (c) first and second projection light source systems that spatially modulate the first and second irradiation lights from the single or plural projection light source systems, respectively, with the irradiation lights from the two sets of writing light source systems; (d) directing first and second illumination lights from the projection light source system to the first and second liquid crystal light valves, respectively; a projection optical system that magnifies and projects the first and second modulated lights; (10) The display device according to claim 9, wherein the plurality of pieces of video information are color-separated video information. (11) The display device according to claim 9, wherein the plurality of irradiation lights are color-separated irradiation lights. (12) The display device according to claim 9, wherein the first and second irradiation lights from the projection light source system are colored lights time-divided in the same order. (13) The display device according to claim 9, wherein the first and second irradiation lights from the projection light source system are colored lights time-divided in different orders. (14) The display device according to claim 9, wherein the first and second irradiation lights from the projection light source system are colored lights that are time-divided at different intervals. (15) The display device according to claims 12, 13, and 14, wherein the time-divided colored lights are red, green, and blue.