JP2586267B2 - Projection display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection type display device such as a projection type projector or a television, and more particularly to a device for changing an image frame of an image projected on a display means in accordance with a type of an incoming image. About.

[0002]

2. Description of the Related Art FIG. 6 is a block diagram of a projection type display device previously filed by the present applicant. This apparatus includes a spatial light modulating element 1 for forming a red image, a spatial light modulating element 2 for forming a green image, a spatial light modulating element 3 for forming a blue image, a three-color combining optical system 4, a first lens group 5, a second , A third lens group 7, and a screen 8.

According to this apparatus, at the time of reproduction, readout light from a light source (not shown) is separated into single light colors of red, green, and blue via a polarizing beam splitter, a dichroic mirror, and the like. Spatial modulation elements 1, 2, 3
Supplied to Then, the images formed on the spatial modulation elements 1, 2, 3 are incident on the three-color combining optical system 4, where the respective images are combined, and the combined image is passed through the first lens group 5. Then, an image is formed on the second lens group 6 at the next stage. The image formed on the second lens group 6 is incident on the third lens group 7 and projected on the screen 8 as an image of a predetermined magnification.
According to this apparatus, the back focus is lengthened, the apparatus can be made thinner, and a high-definition image can be obtained.

[0004]

According to the spatial light modulator of the optical writing type as described above, the size, shape or aspect ratio of the image frame can be freely adjusted according to the type of the incoming image. It is possible to change and record. However, since the readout light from the light source is uniformly applied to the effective area, the light is also applied to the outside of the required screen, and the outside of the screen on the screen becomes bright due to unnecessary light such as surface reflection of the substrate. There was a problem of becoming.

In this case, it is conceivable to provide an aperture in which a predetermined opening is formed on the light-shielding surface to block unnecessary light to enhance the contrast inside and outside the screen. But,
In the case where the aperture of the aperture has a fixed structure, for example, when an image with a larger image frame than expected is received, it is not possible to cope with the problem and a necessary image portion is cut off. was there. The problem to be solved by the present invention is to solve such a problem.

[0006]

SUMMARY OF THE INVENTION The present invention provides the following structure to solve the above-mentioned problems. That is, in a projection display device in which image information written in a spatial modulation element is read as an optical image by a light source and this optical image is projected through a lens group, the optical information is provided near an image forming plane in the lens group. A projection type display device comprising a mask means for blocking unnecessary light in a projection light beam including an image, and a changeable shape of the mask means.

[0007]

An optical image is read from a spatial modulation element, and a mask means for blocking unnecessary light in a projection light beam including an optical image is provided in the vicinity of an image forming plane in a lens group, so that a sharp image of an image frame is formed. In addition to projecting, the shielding shape of the mask means can be changed so that even if an image with a different image frame comes in, it can be handled.

[0008]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a projection display device according to a specific example of the present invention. In the figure, 10 is a signal source,
For example, an NTSC television signal is generated and supplied to the serial / parallel conversion circuit 11, where the time-series signal is converted into a simultaneous signal. As the serial-parallel conversion circuit 11, for example, a shift register can be used.

[0009] The video signal converted into the simultaneous signal is supplied to the light emitting means 12 at the next stage. This light emitting means 1
Reference numeral 1 denotes a light emitting element array in which a plurality of light emitting element arrays are arranged in series, and emits light at an intensity corresponding to an incoming signal. Light beams emitted by these elements are polarized by the polarizer 13 and enter the spatial modulation element 15 via the lens 14. And
Here, an image based on the incident light is formed.

At this time, at the same time, the other spatial modulation elements 16, 1
7 is also formed with an image. The configuration from the signal source 10 to the spatial modulation elements 16 and 17 has the same function as the configuration from the spatial modulation element 15 to the spatial modulation element 15, and therefore, illustration and description are omitted.

The spatial modulation elements 15, 16, 17
2 have the same configuration, and FIG. 2 shows a specific configuration diagram of the spatial modulation element 15 which is one of them. As shown in the figure, the spatial modulation element 15 includes a glass substrate 15a, a transparent electrode E1, a photoconductive layer member 15b, a dielectric mirror 15c, and a light modulation layer member 15d (for example, a TN liquid crystal, a vertically aligned liquid crystal, or the like). A light modulation layer utilizing the birefringence effect), a transparent electrode E2,
And a glass substrate 15e are sequentially laminated.

When writing an image, a voltage is applied to the transparent electrodes E1 and E2, an electric field is generated at both ends of the photoconductive layer member 15b, and writing light (image light) WL enters from the transparent electrode E1 side. Let it do. As a result, the incident write light WL passes through the transparent electrode E1 and reaches the photoconductive layer member 15b.
The electrical resistance value of b changes according to the intensity distribution of the writing light WL.

[0013] When reading the data, a reading light RL is incident. Thus, in the light modulating layer, the read light RL is modulated according to the change state of the write light WL, reflected by the dielectric mirror 15c, and read from the transparent electrode E2 side.

Referring again to FIG. 1, the spatial light modulator 1
The images formed on 5, 16, and 17 are read out by the reading light RL in real time. This read light RL is transmitted from a light source 27 to a polarization beam spiriter 28.
Is irradiated. Linearly polarized light (S wave) of this incident light
Is incident on the three-color separation / combination optical system 29 side by the vapor deposition surface 28a.

Further, green light of this linearly polarized light (S wave) passes through the dichroic filters 29a and 29b and enters the spatial light modulator 16. The red light passes through the dichroic filter 29a, is reflected by the dichroic filter 29b in a right angle direction, and enters the spatial light modulator 17. Further, the blue light is reflected by the dichroic filter 29a in a right angle direction and enters the spatial light modulator 15. As a result, the image formed on each of the spatial light modulators 15, 16, and 17 is read by these incident lights, and the dichroic filter 2 is again read.
The light is supplied to the three-color separation / combination optical system 29 via 9a and 29b, where it is converted into three-color combined image light.

The image light composed of the three colors is incident on the polarization beam spiriter 28, and only the P-wave component is transmitted therethrough. The image light from the polarizing beam spiriter 28 is incident on the first lens group 30, the amount of light is reduced by the stop 31, and the image light of the next stage is imaged on the second lens group 32. . Then, the image light is
An extra light beam on the outside is blocked by an aperture (mask means) 33 which is provided on the subsequent stage of the lens group 32 and is a main part of the present invention.

FIG. 3A is a perspective view showing a specific structure of the aperture 33. As shown in FIG. As shown in FIG.
3 is a glass substrate 33a, a polarizing plate 33b that allows only the P wave component to pass, an aperture 33c, a TN liquid crystal 33d, a transparent electrode E3, and a polarizing plate 33e that allows only the S wave component to pass.
And the glass substrate 33f are sequentially laminated.

FIG. 3B is a schematic plan view of the aperture 33c. In the figure, a (a shaded portion) is a shielding portion, b, c, d, and e (a satin pattern portion) are transparent electrode portions, and f is an opening. The rectangle formed by the opening f and the transparent electrode parts b and e has an aspect ratio of 3 to 4. The rectangle formed by the opening f and the transparent electrodes c and f has an aspect ratio of 9:16.

As described above, NTSC image light having an aspect ratio of 3 to 4 enters the aperture 33 as described above.
A voltage is applied to the transparent electrode portions b and d of the tea portion 33c, and no voltage is applied to the transparent electrode portions c and e. Therefore, T
Light is transmitted from portions of the N liquid crystal 33d corresponding to the transparent electrode portions b and d, and conversely, light is not transmitted from portions corresponding to the transparent electrode portions c and e. Therefore, here, the extra outer light flux that has spread more than necessary is cut off, and only 3 to 4 necessary image light is obtained.

Then, this image light is incident on the third lens group 34 at the next stage, where the light amount is narrowed down by a stop 35, and an enlarged optical image is projected on a screen 36. The image at this time has an aspect ratio of 3 because extraneous external light is blocked by the aperture 33.
The image is defined as a sharp image with a pair of four image frames.

Further, when a television signal having an image frame different from that of the NTSC system and having an aspect ratio of 9 to 16 is supplied from the signal source 10, the signal is not shown. Turn on the operation switch for changing the screen ratio. As a result, a voltage is applied to the transparent electrode portions c and e, and no voltage is applied to the transparent electrode portions b and d. In this case, light is transmitted from portions corresponding to the transparent electrode portions c and e in the TN liquid crystal 33d, and conversely, light is not transmitted from portions corresponding to the transparent electrode portions b and d. Then, as in the above case, the extra outer light beam is blocked here, and the aspect ratio becomes 9:16.
Will be displayed on the screen 36. The TN liquid crystal 33d may have a configuration in which liquid crystal is dispersed in a polymer instead of the TN liquid crystal 33d, and a transparent electrode may be formed in the opening f for the configuration of the aperture 33c. A projection shutter structure that can block projection light may be used.

FIG. 4 shows another embodiment of the aperture 33.
Four shielding plates, h, i, j, and
k are provided movably in the directions of the arrows. In the normal state before the movement, the opening g is provided so that the aspect ratio is 3: 4, and at the movement end position, it is 9:16. This moving structure does not need to use a special structure, and may be a known structure using a stepping motor or the like, and illustration thereof is omitted.

FIG. 5 shows still another embodiment of the aperture 33, in which one shielding plate m has an opening n having an aspect ratio of 3: 4 and an opening o having a 9:16 ratio. It is formed and moved in the direction of the arrow in response to an incoming signal. In this case, the moving structure does not need to be a special structure as in the above case, and may be a known structure. In each embodiment of the aperture, the aperture
It is needless to say that if the light shielding shape of the tea is changed, it can be applied to various image information.

In the apparatus of this embodiment, the type of the signal information from the signal source 10 is recognized by the operator and the operation switch is turned on manually. However, the present invention is not limited to this. A connector corresponding to the source is provided, and when the corresponding connector is connected, a switch is turned on to apply a voltage to any of the transparent electrode portions b, c, d, and e, or to move each shielding plate. It may be configured. Further, a configuration may be adopted in which signal information is detected electrically or optically, and the light shielding shape is deformed based on the information. In the case where these configurations are adopted, the operation of the operation switch is forgotten, and the operation time is saved.

As described above, when the apparatus of this embodiment is used, even if an image signal having a different image frame is received, an extra light beam can be trimmed by a light-shielding shape corresponding to the image signal. A sharp image can be displayed on the screen.

[0026]

According to the projection display apparatus of the present invention, the image information written in the spatial modulation element is read out as an optical image by a light source, and the optical image is projected through a lens group. A mask means for blocking unnecessary light in the projection light beam including the optical image is provided in the vicinity of the image forming plane in the lens group, and a configuration in which a blocking shape by the mask means is provided so as to be changeable is provided. Even if different image signals are received, an extra light beam can be trimmed by the light-shielding shape corresponding to the different image signals, so that a sharp image of a contrasting image frame can be displayed on a screen.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a projection display device according to a specific example of the invention.

FIG. 2 is a specific configuration diagram of a spatial modulation element 15.

FIG. 3A is a perspective view of an aperture 33. FIG.
(B) is a schematic plan view of the aperture section 33c.

FIG. 4 shows a second embodiment of the aperture 33.

FIG. 5 shows a third embodiment of the aperture 33;

FIG. 6 is a configuration diagram of a conventional projection display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Signal source 11 Serial-parallel conversion circuit 12 Light emitting means 13 Polarizer 14 Lens 15, 16, 17 Spatial modulation element 27 Light source 28 Polarization beam splitter 29 Three-color separation / synthesis optical system 30 First lens group 32 Second lens Group 33 aperture (mask means) 34 third lens group 36 screen

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Ryusaku Takahashi 3-12-12 Moriyacho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Inside of Victor Company of Japan, Ltd. (72) Hiroyuki Bonide 3-12 Moriyacho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Address: Japan Victor Co., Ltd. (72) Inventor Tsutomu Matsumura 3-12 Moriyacho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Examiner of Victor Company of Japan Toshiaki Tsuda

Claims (1)

(57) [Claims] 1. A projection display device for reading out image information written in a spatial modulation element as an optical image by a light source and projecting the optical image through a lens group. And a masking means for blocking unnecessary light in the projection light beam including the optical image, and a shape of the masking means can be changed so as to be changeable.