JP2003043575A - Projection type image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projection type image display device in which a fixed image formed on a screen surface does not hinder visibility at the time of projecting an image. SOLUTION: In the projection type image display device 1 in which a display image is projected from an image projector 3 onto a rear surface of a semitransparent plate 41 and the display image is visualized from a surface of the semitransparent plate 41, a semitransmissive fixed image 42 is provided on a surface of the semitransparent plate 41 and a complementary image 43 transmitivity of which is complementary to the fixed image 42 is provided on a rear surface of the semitransparent plate 41. The fixed image 42 and the complementary image 43 compensate each other and thereby transmitivity of a screen 4 becomes almost constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection type image display device for projecting an image from the back side of a screen.

[0002]

2. Description of the Related Art Conventionally, in a projection type image display device,
Nothing is reflected on the screen surface when it is not projected, and it is a black uniform surface. Therefore, it is possible to draw letters and pictures on the screen to improve the appearance. For example, as shown in FIG. 11, by forming a fixed image 203 such as characters and pictures on the surface of the screen 200 by printing dots, stripes, or the like on a transparent sheet, the fixed image 203 is visually recognized during non-projection, On the other hand, at the time of image projection, display is performed in the gap between the stripes so that the projected image 202 can be visually recognized.

[0003]

However, when a display image is projected from the back surface onto a screen on which a fixed image such as a character or a picture is formed, the fixed image such as a character or a picture formed on the front surface of the screen interferes with the display image. Therefore, there is a problem that the projected display image is difficult to see.

The present invention has been made in view of the above problems, and an object thereof is to provide a projection-type image display device in which a fixed image formed on a screen surface does not hinder the visibility during image projection. That is.

[0005]

The invention according to claim 1 is
In order to achieve the above object, in a projection type image display device for projecting a display image on the back surface of a semitransparent screen and visually recognizing the display image from the front surface of the screen, a semitransparent fixed image is provided on the front surface of the screen. A complementary image whose transmittance is complementary to the fixed image is provided on the back surface of the screen, and the fixed image and the complementary image cancel each other out so that the transmittance of the screen becomes substantially constant. Use as a summary.

In order to achieve the above object, the invention according to claim 2 provides the projection type image display device according to claim 1,
The gist is that gradation is provided at the end of the fixed image and the end of the complementary image.

In order to achieve the above object, the invention according to claim 3 is the projection type image display apparatus according to claim 1 or 2, wherein the back surface of the screen is a semi-transmissive image having the pattern of the complementary image. The point is to install a filter.

According to a fourth aspect of the present invention, in order to achieve the above object, in the projection type image display apparatus according to any one of the first to third aspects, the fixed image and the complementary image are: It is a gist to have a complementary color relationship at the same position on the screen surface.

In order to achieve the above object, the invention according to claim 5 is the projection type image display apparatus according to any one of claims 1 to 4, wherein the screen surface and the fixed image are arranged between the screen surface and the fixed image. The gist is that a louver is provided.

In order to achieve the above object, the invention according to claim 6 is the projection type image display device according to any one of claims 1 to 5, wherein the screen has a curved surface shape and the fixed image. The gist of the above is to determine the positions of the complementary image and the complementary image according to the direction of the projection light of the projected image and the curvature of the screen.

In order to achieve the above object, the invention according to claim 7 is the projection type image display device according to any one of claims 1 to 6, wherein the fixed image is a shape or pattern around the screen. The gist is that it should be adapted to.

[0012]

According to the invention described in claim 1, in a projection type image display device for projecting an image on the back surface of a semitransparent screen and visually recognizing the image from the front surface of the screen, a semitransparent screen is provided on the front surface of the screen. Providing a transparent fixed image,
A complementary image whose transmittance is complementary to that of the fixed image is provided on the back surface of the screen, and the fixed image and the complementary image cancel each other so that the transmittance of the screen becomes substantially constant. Therefore, when non-projection, characters and pictures by the fixed image on the screen surface are visually recognized, and the appearance is improved.When the image is projected, the transmittance of each part of the screen becomes the same, so the characters and pictures by the fixed image that were visible during non-projection are displayed. The effect is that the picture is canceled and the projected image is visible.

According to the second aspect of the invention, in addition to the effect of the first aspect of the invention, gradation is provided at the end of the fixed image and the end of the complementary image, so that a screen is displayed. Even if the fixed image on the front surface and the complementary image on the back surface of the screen are misaligned, the fixed image and the complementary image are canceled with each other with high accuracy, and the projected image can be recognized more clearly.

According to the invention of claim 3, in addition to the effect of the invention of claim 1 or 2, a semi-transmissive filter having the pattern of the complementary image is provided on the back surface of the screen. As a result, even when the image is projected, the transmittances of the respective parts of the screen become equal, so that the characters and pictures of the fixed image that were visible when the image was not projected are canceled, and the projected image can be visually recognized.

According to the invention of claim 4, in addition to the effect of the invention of claims 1 to 3, the fixed image and the complementary image have a complementary color relationship at the same position on the screen surface. Therefore, even when the fixed image on the screen surface is displayed in multiple colors, the fixed image on the screen surface can be canceled at the time of projection, and the projected image can be visually recognized.

According to the fifth aspect of the invention, in addition to the effects of the first to fourth aspects of the invention, a louver is provided between the screen surface and the fixed image, so that a projected image is formed. There is an effect that window reflection and external light can be prevented from entering the screen.

According to the invention of claim 6, in addition to the effects of the invention of claims 1 to 5, the screen has a curved shape, and the positions of the fixed image and the complementary image are projected. Since it is decided according to the direction of the projected light of the image and the curvature of the screen, the effect that the fixed image and the complementary image are accurately canceled at the time of projection even on a screen having a curved surface, and a beautiful projected image can be displayed There is.

According to the invention of claim 7, in addition to the effects of the invention of claims 1 to 6, since the fixed image is adapted to the shape and pattern around the screen, non-projection At times, it is possible to create a sense of unity between the instrument surface and the screen surface, which has the effect of improving the texture.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will now be described in detail with reference to the drawings.

[First Embodiment] FIG. 1 is a diagram showing a vehicle-mounted configuration of a first embodiment of a projection type image display apparatus according to the present invention. In FIG. 1, the projection-type image display device 1 includes an image data generation unit 2 that receives vehicle information, a navigation device, a camera, information from the outside, and the like, and generates image data to be displayed, and an image data generation unit 2. The image projection device 3 for converting the image data generated by the above into a projection image, and the screen 4 on which the fixed image 42 is formed on the front surface of the semitransparent plate 41 and the complementary image 43 is formed on the back surface by printing or the like.

The semi-transparent plate 41 may be one in which light-reflecting fine particles are diffused all over, or may be one which is made semi-transparent by providing minute irregularities in the shape of frosted glass on the surface of the transparent plate. The image projection device 3 is a rear projection image display device that projects an image from the back surface of the screen 4 and observes the image from the eyepoint 5 on the front surface side of the screen 4. Screen 4
Is a fixed image 42 such as letters and pictures on the surface of the translucent plate 41.
Is formed, and on the back surface of the semitransparent plate 41, a complementary image 43 whose transmittance is complementary to that of the fixed image 42 is formed. Thereby, the fixed image 42 and the complementary image 43 cancel each other out, and the transmittance of the screen 4 becomes substantially constant, which is a feature of the present invention.

When the image projection device 3 does not project an image on the screen 4, the fixed image 42 formed on the surface of the screen 4 is visually recognized. On the other hand, at the time of projection in which the image projection device 3 projects an image on the screen 4, the fixed image 42 formed on the front surface of the screen 4 and the complementary image 43 formed on the back surface thereof cancel each other out, and the transparent image of the screen 4 is transmitted. The ratio becomes substantially constant, and the image projected from the image projection device 3 is transmitted and diffused by the screen 4 to be a visible image.

FIG. 2 shows a detailed configuration example when a DMD (digital micromirror device), an LCD (liquid crystal display device), or a reflection type LCD is used as the image projection device 3 of the first embodiment. It is a block diagram.

In FIG. 2, the image projection device 3 includes an image control unit 110, a light source control unit 130, and a color separation control unit 14.
0, the display element control unit 150, the light source unit 131, the color separation filter 132, the integrator 141, the light deflection unit 151 as a display element, and the image formed by the light deflection unit 151 is projected on the screen 4. And a projection optical system 160. Other configurations are the same as those shown in FIG.

The image control unit 110 includes an image data generation unit 2
The light source control unit 130, the color separation control unit 140, and the display element control unit 150 are controlled by receiving the signal from the.

Next, the operation of the present invention will be described in detail with reference to FIG. Image data generation unit 2 that receives vehicle information, navigation, cameras, external information, etc.
The image data from is sent to the image controller 110. The image control unit 110 controls the light source control unit 130, the color separation control unit 140, and the display element control unit 150 according to the image to be displayed.

Reference numeral 131 denotes a light source section, which is a light source control section 13
It receives a signal from 0 and emits white light. The color separation filter 132 is a filter for color-separating the light emitted by the light source unit 131 into three primary colors of RGB, and the color separation control unit 14
Controlled by 0. Note that, here, the light source that includes the components of the three primary colors is used to perform the color separation by the filter to form the light source of the three primary colors. However, the light source unit 131 and the color separation filter 132 independently of the three primary colors. A light source such as a light emitting diode that emits light may be used and each light source may be independently turned on. Integrator 141
Is an integrator for collimating the light from the light source unit 131, and the light deflection unit 151 is an integrator 1.
It is a light deflecting means for deflecting the light from 41 according to the image data, and a DMD, an LCD, a reflective LCD or the like can be used. The projection optical system 160 is a lens group that magnifies and projects the light from the light deflection unit 151 to project it on the screen 4.

The light emitted from the light source 131 is separated into the three primary colors of light by the color separation filter 132. The light that has passed through the color separation filter 132 emits the three primary colors in time series, and is collimated by the integrator 141, and the light deflector 1
Reach 51. The display element control unit 150 receives the signal from the color separation control unit 140, and according to the image data of the color emitted from the color separation filter 132, the light deflection unit 15.
On / Off of each display element of No. 1 is controlled. The light of dots of which each display element is On passes through the projection optical system 160 and is projected on the screen 4. On the contrary, the Off dots are not projected and are visually recognized by the driver as On / Off pixels. By this control, a desired image can be projected on the screen 4.

Next, the effect of the screen used in this embodiment will be described. FIG. 3 shows the screen configuration of this embodiment. Further, FIG. 4 is a diagram showing a display example when the present invention is used. The screen 4 for diffusing the projected image is formed by printing a translucent plate 41 for transmitting and diffusing the projected image so that the driver can visually recognize the translucent plate 41 and a surface on the driver side of the translucent plate 41. The fixed image 42 and the complementary image 43 formed by printing or the like on the back surface of the semitransparent plate 41 on the image projection device 3 side. This screen 4
When the image is not projected from the image projection device 3 side, as shown in FIG. 3A, when the external light hits the screen surface, the portion where the image is formed (printing portion) and the image is formed. The degree of diffusion of extraneous light differs between the non-printed portion (non-printed portion). Thereby, for example, the pattern as shown in FIG. 4A is visually recognized by the driver.

On the other hand, the back surface of the semitransparent plate 41, which is the image projection device 3 side, has a high transmittance at a portion where the transmittance is reduced due to printing on the front surface, and a transmittance which is not printed. A print with a low transmittance is applied to a high portion to form a complementary image 43 to the fixed image 42 on the surface.
At this time, the front surface and the back surface are printed so that the transmittances of the respective parts of the screen 4 are equal.

For example, with respect to the printing on the surface as shown in FIG. 4A, printing is performed by inverting the printing on the surface as shown in FIG. This gives, for example,
When uniform projection is performed on the entire screen from the image projection device 3 to the screen 4, the printing on the surface disappears and a uniform projected image is visually recognized on the entire screen as shown in FIG. 4C. To be done. Therefore, even when a desired projection image is projected from the image projection device 3, the projection image can be visually recognized without being significantly affected by the printing on the front surface, and the quality of the display image is less likely to deteriorate.

At this time, the display image projected from the image projection device 3 has a higher brightness than the external light and has a predetermined contrast or more so that the display image can be visually recognized. In addition, the brightness sensor detects the intensity of extraneous light, and when the extraneous light becomes weak, such as at night, by reducing the brightness of the projected image while maintaining a predetermined contrast or higher, the nighttime annoyance is reduced. It goes without saying that the above can be reduced.

FIG. 7 is an image diagram showing the effect of the projection type image display device of the present invention. During non-projection, as shown in FIG. 7 (a), the display 76 by printing on the screen surface is visually recognized to give a sense of unity with the design of the instrument panel. On the other hand, when an image is projected, the printing on the front side and the printing on the back side cancel each other, so that only the projected image is visible.

In the example of FIG. 7B, the air conditioner display 71,
An audio display 72, a car navigation screen display 73, a speedometer display 74, and a shift position display (AT selector display) 75 are displayed.

As a result, even when an image is not displayed on the screen of the projection type image display device during parking or the like, the display of a fixed image such as characters and pictures can be visually recognized on the screen, and the instrument design can be destroyed. Absent. On the other hand, it is possible to obtain the effect that the display image can be properly visually recognized even when the image is projected. Further, the present invention is effective as the screen becomes larger.

[Second Embodiment] Next, a second embodiment will be described. FIG. 5 is an enlarged image view of the screen 4. For example, the fixed image 42 by front surface printing or the like and the complementary image 43 by back surface printing or the like are configured such that the bright portion and the dark portion are staggered as shown in the figure.

At this time, in a pattern in which the printing transmittance changes abruptly, as shown in FIG. 5A, the fixed image 42 by printing on the front surface and the complementary image 43 by printing on the back surface are formed.
In the case where the overlapping positions occur and the overlapping positions occur, as shown in FIG. 5B, the transmittance of the overlapping portion 60 becomes lower than that of the surrounding portion, and the portion is emphasized.

On the other hand, if a gap is created, the transmissivity is higher than that of the surroundings, and a display that is partially brighter than the surroundings is displayed. Therefore, in this embodiment, as shown in FIGS. 6A and 6B, the gradation portions 42 (a), 42 (b), and
The so-called gradation process of providing 43 (a) and 43 (b) is performed so that the transmittance gradually changes.

As a result, it is possible to prevent the transmittance from changing abruptly, so that the tolerance of printing position deviation between the front surface and the back surface becomes large, so that the tolerance for printing accuracy becomes large and the cost of printing is reduced. Is possible.

[Third Embodiment] Next, a third embodiment will be described. FIG. 8 is a cross-sectional view showing the configuration of the screen according to the third embodiment. The fixed image 44 is
It is a filter made of a transparent film which is partially colored in a predetermined color in the form of letters or patterns, and is provided on the surface of the semitransparent plate 41. Further, the complementary image 45 has the same pattern as the fixed image 44 on the transparent film and the fixed image 4 on the surface.
The same portion of 4 is a filter colored in a complementary color relationship. Other configurations are similar to those of the first embodiment.

Similar to the first embodiment of the present invention, when the external light reaches the surface during non-projection, the external light is incident on the fixed image 44 by the filter and is reflected and diffused by the semitransparent plate 41. By doing so, the color of the filter of each part is visually recognized by the driver, and as a result, the fixed image 44 such as characters and patterns provided on the surface filter can be visually recognized.

On the other hand, when the display image is projected from the image projection device 3, since the front and back filters have complementary colors, the projected image has the same color components at any part on the screen. Attenuated. For example, when the red and blue components are attenuated by the surface filter, the green component is transmitted and the reflected light on the surface is green.
So, on the back surface of the same part as the green filter on the front surface,
Provide a filter that attenuates green. by this,
For example, when white is projected from the image projection device 3, the green color component is attenuated by the filter on the back surface. In addition, the surface filter attenuates the red and blue color components,
Since all color components are attenuated similarly, the visible display light is a white or gray achromatic color.

As described above, the influence of the front surface filter on the display light is suppressed by the back surface filter, and the image originally intended to be displayed can be visually recognized. As described above, the same effect can be obtained even if the pattern applied to the surface is color. The filter according to the present embodiment may have an optical characteristic of attenuating a predetermined wavelength, or may have a semi-transmissive print.

Further, instead of providing the filter on the back surface, the same effect can be obtained by processing the display light to be projected in advance in accordance with the pattern of the filter on the front surface. For example, when a filter that attenuates the green color component is provided on the surface, among the display light projected from the projector, the red and blue color components of the display light corresponding to the portion where the filter is provided on the surface By attenuating and projecting, the transmitted light that passes through the screen and is viewed by the driver is attenuated similarly to each color, and is viewed as an achromatic color of white or gray.

[Fourth Embodiment] Next, a fourth embodiment of the present invention will be described. In FIG. 9, a louver 46 is provided on the driver side of the translucent plate 41 of the screen 4 to limit the traveling direction of light to a direction substantially perpendicular to the screen surface, and a fixed image 42 is printed on the surface of the louver 46 by printing or the like. Is formed. The configuration other than this is the same as that of the first embodiment.

According to this embodiment, since the direction of the light emitted from the screen 4 is regulated by the louver 46, the display light diffused by the semitransparent plate 41 is reflected by the front window and visually recognized by the driver. It is possible to prevent so-called window reflection. As a result, it is possible to reduce the annoyance without hindering the front view of the driver. Further, as shown in FIG. 10, even when the filter 44 is used as the fixed image, the same effect can be obtained by providing the louver 46 between the filter 44 and the diffusion surface.

Furthermore, in each of the above-described embodiments, the screen of the present invention can have not only a flat surface but also a curvature. Further, when the display light from the image projection device 3 is incident on the screen 4 at an angle, the positions of the fixed image and the complementary image (printing on the front surface and the back surface or the filter) according to the present invention are considered in the directionality of the projection light. It is necessary to correct the position. On the contrary, when the display light from the projection device is radially emitted, it is possible to use a screen having a curvature such that the display light is vertically incident at any position on the screen.

Further, by providing a Fresnel lens on the image projection device side of the printing on the back side or the filter so that the display light enters the screen perpendicularly to the screen, the positions of the printing on the front side and the back side or the position of the filter are set. It is also possible to facilitate the alignment.

As described above, in the projection device for presenting an arbitrary image and the rear projection type display device in which the display light from the projection device is transmitted and diffused to be visually recognized by the driver, Desired character,
By printing a pattern or pattern or providing a filter, and by printing on the back side of the screen to erase the characters, pattern or pattern on the screen, or by providing a filter, the pattern on the screen surface can be protected by external light when not projecting. It is visually recognized and presents predetermined characters and patterns,
It is possible to produce a sense of unity with the instrument design. Further, when the display light is projected, the pattern on the front surface is canceled by the printing or the filter on the back surface, and it becomes possible to prevent the projected display light from being affected so much.

Furthermore, the effect of being able to be applied to a color pattern can be obtained by printing on the front surface and the back surface or by making the filters have a complementary color relationship.

Further, by applying gradation or the like so that the transmittance of the pattern applied to the front surface and the back surface does not change abruptly, it is possible to improve the tolerance for the printing on the front surface and the back surface or the positional deviation of the filter. Is obtained.

In addition, with respect to the displacement of the back surface from the front surface,
The position shift can be prevented by correcting the position in consideration of the incident angle of the display light to the screen. On the contrary, by making the screen have a curvature that matches the incident angle of the display light, or by inserting an optical element such as a Fresnel lens between the back surface and the projection device to make the incident angle to the screen vertical. Also, the effect that the position can be easily corrected can be obtained.

Further, although the projection type display is used in the above embodiment, any display device which projects light from the rear surface and deflects the light to project a display image can be applied. For example, in a liquid crystal display in which a backlight is deflected by a liquid crystal cell to perform dot On / Off, a filter corresponding to the back surface may be provided between the backlight on the back surface and the liquid crystal panel, and a filter may be provided on the front surface of the liquid crystal panel. The same effect can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic view showing a vehicle-mounted state of a first embodiment of a projection-type image display device according to the present invention.

FIG. 2 is a block diagram illustrating details of the projection-type image display device according to the first embodiment.

FIG. 3 is a cross-sectional view showing the configuration of the screen according to the first embodiment.

FIG. 4 is a diagram showing an effect of the present invention in the first embodiment.

FIG. 5 is a cross-sectional view illustrating an influence of positional deviation between a fixed image and a complementary image according to the first embodiment.

FIG. 6 is a cross-sectional view showing a configuration of a screen according to a second embodiment.

FIG. 7 is a diagram illustrating a display example of the first embodiment.

FIG. 8 is a sectional view showing a configuration of a screen according to a third embodiment.

FIG. 9 is a sectional view showing a configuration of a screen according to a fourth embodiment.

FIG. 10 is a sectional view showing a configuration of a screen according to a fourth embodiment.

FIG. 11 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

1 ... Projection type image display device 2 ... Image data generator 3 ... Image projection device 4 ... Screen 41 ... Semi-transparent plate 42 ... Fixed image 43 ... Complementary image

Continued front page    (72) Inventor Masao Sakata             Nissan, Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan             Inside the automobile corporation F-term (reference) 2H021 BA21 BA28

Claims (7)

[Claims] 1. A projection type image display device for projecting a display image on the back surface of a semitransparent screen and visually recognizing the display image from the front surface of the screen, wherein a semitransparent fixed image is provided on the front surface of the screen, A complementary image whose transmittance is complementary to the fixed image is provided on the back surface of the screen, and the fixed image and the complementary image cancel each other, and the transmittance of the screen becomes substantially constant. Projection image display device. 2. The projection type image display device according to claim 1, wherein gradations are provided at an end of the fixed image and an end of the complementary image. 3. The projection type image display apparatus according to claim 1, wherein a semi-transmissive filter having the pattern of the complementary image is installed on the back surface of the screen. 4. The projection type image according to claim 1, wherein the fixed image and the complementary image have a complementary color relationship at the same position on the screen surface. Display device. 5. The projection type image display device according to claim 1, wherein a louver is provided between the screen surface and the fixed image. 6. The screen has a curved surface shape, and the positions of the fixed image and the complementary image are determined according to the direction of the projection light of the projection image and the curvature of the screen. The projection-type image display device according to claim 5. 7. The fixed image is adapted to a shape and a pattern around the screen.
7. The projection-type image display device according to claim 6.