JP4378865B2 - Projector device and image quality improvement mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a projector apparatus such as a data projector or a video projector.
[0002]
[Prior art]
Devices that project or project images such as data projectors and video projectors use white light sources such as xenon lamps, high-pressure mercury lamps, and metal halides, and use small image display devices (light valves) such as liquid crystals and micromirror devices. A desired image is projected onto a reflective or transmissive screen by a lens system configured by modulating light and using a plurality of lenses or prisms.
[0003]
[Problems to be solved by the invention]
Such a projector device is required to display a compact, bright and beautiful image. For this reason, the light-emitting part of the light source is further reduced so as to be compact and improve the light efficiency. As a result, the coherence increases and the speckle pattern appears strongly on the screen. Yes.
[0004]
A speckle pattern is a spot-like pattern with high contrast generated on a screen when the screen or the like is illuminated with coherent light. A speckle pattern is a complex interference pattern that occurs when light scattered at each point on the screen interferes with each other in an irregular phase relationship. Is recognized as noise. Therefore, in a device that projects an image on a screen, such as a projector, speckle noise caused by the coherence of light gives the impression that the image quality has deteriorated. It is required to do.
[0005]
Further, in a projector device that can display a compact and high-quality (high gradation) image, a light valve (image display device) such as a compact and high-resolution liquid crystal panel is used. When a high resolution and compact size is achieved, the pixel that is a unit element constituting the screen in the image display device is subdivided (reduced), so that it approaches the wavelength level of light, and as a result, the light emitted from the image display device The coherence of (emitted light) is increased, and speckle noise is easily generated on the screen as described above even if it is caused by these.
[0006]
In addition, for viewing movies and other movies, there is a great demand for rear-type projectors that are integrated with a transmissive screen, and in order to obtain a bright image, a highly directional output light such as a hologram screen is used. Has been. In such a screen, coherence is increased because the light beam is aligned with a thin light flux in order to increase directivity, and speckle noise is likely to be noticeable, and the image quality of the displayed image is degraded.
[0007]
In this way, in recent years, the development of compact projectors capable of displaying high-resolution images is essential to reduce speckle noise in order to create compact, high-quality images. It has become.
[0008]
Therefore, an object of the present invention is to provide a projector device and an image quality improvement mechanism that can project a bright and high-quality image with a compact configuration while suppressing speckle noise.
[0009]
[Means for Solving the Problems]
For this reason, in the present invention, an optical component that gives a slight optical path difference to the emitted light is arranged on the optical path from the image display device to the screen, and various speckle patterns are generated by moving it with the driving means. Speckle noise visible on the screen is reduced as they are time mixed on the retina.
[0010]
That is, the image quality improvement mechanism of the present invention is disposed on the optical path from the image display device of the projector apparatus to the screen that modulates the light from the light source with the image display device and projects the light onto the screen via the lens system. And an optical component that generates an optical path difference distribution that does not affect the image displayed on the screen, and a drive unit that moves the optical component so that the optical path difference distribution varies with time. Further, the projector device according to the present invention has this image quality improvement mechanism, that is, a light source, an image display device capable of modulating light from the light source, and light from the image display device on a screen. Lens system to project, optical components that are placed on the optical path from the image display device to the screen and generate an optical path difference distribution that does not affect the image displayed on the screen, and the optical path difference distribution varies over time And a driving means for moving the optical component.
[0011]
In the projector apparatus and the image quality improvement mechanism of the present invention, there is an optical path difference distributed to such an extent that the optical component (optical element) does not affect the image on the optical path, that is, the diffraction angle is sufficiently small. Speckle patterns appearing on the screen increase due to light emitted from the image display device toward the screen. Then, since the optical component is moved by the driving means, these various speckle patterns are superimposed, and an image in which these speckle patterns are time-integrated and mixed is recognized on the retina. For this reason, the intensity of each speckle pattern is weakened, and images obtained by integrating them with time are recognized. As a result, the distribution of coherence is suppressed and speckle noise that can be recognized by humans on the screen can be reduced. For this reason, even in a projector device that projects light with high coherence in order to achieve a compact and high resolution, it is possible to project a high-quality image by reducing speckle noise and display a bright and beautiful image. it can.
[0012]
In a projector apparatus that can display a compact and high-resolution image, as described above, not only the light source but also the image display device is a factor that increases the coherence. Therefore, by arranging the optical component of the image quality improvement mechanism behind the image display device, that is, on the optical path on the screen side, it is possible to reduce speckle noise due to light modulated by the image display device, It is possible to solve the problem of speckle noise in the projector apparatus which is compact and high performance as a whole.
[0013]
Further, by arranging the optical component on the optical path from the image display device to the screen, several merits can be obtained. By disposing the optical component on the screen side of the lens system, the image quality improvement mechanism can be introduced without affecting the optical system from the light source to the lens system. For this reason, it is possible to provide a compact projector device that can reduce the time and effort required to change the design associated with the introduction of the image quality improvement mechanism and can display high-quality images at low cost. It is also possible to provide an image quality improvement mechanism that can be installed as an option in existing or future projector devices.
[0014]
Also, in the optical system from the light source to the image display device, especially when a liquid crystal is adopted as the image display device or a dichroic prism is used, it is telecentric to prevent the angular dependence of these optical elements from appearing. Whereas the system is employed, there is a stop position where the light beam is focused on the optical path from the image display device to the screen. Therefore, the optical components that generate the optical path difference are arranged in the vicinity of the stop position, so that the optical components can be gathered in a compact manner. To provide a projector apparatus that can display a clean image with a compact overall position including an image quality improvement mechanism by disposing an optical part in the lens system in many cases. Can do.
[0015]
In order to efficiently increase the number of speckle patterns, which are coherent patterns, in the visible light region, the image quality improvement mechanism of the present invention has an optical path difference of about one wavelength or less of the image display device with respect to the light in the visible light region. It is desirable to generate Therefore, it is desirable to generate an optical path difference of about one wavelength or less with respect to the light in the visible light region at the portion of the optical component that transmits or reflects the light flux from the image display device to the screen. In order to generate an optical path difference, a method of providing unevenness that generates a step of about the wavelength of light in the visible light region or less, or doping iodine, or the like, a method of reducing the wavelength of light in the visible light region or less. Regions having different refractive indexes can be distributed so as to generate an optical path difference.
[0016]
In addition, the driving means can rotate or reciprocate the optical component in order to change the distribution of the optical path difference with time, and the optical component is more than about 24 to 30 Hz, which is higher than the resolution of human vision. By moving at high speed, various speckle patterns can be mixed on the retina so that they are not individually recognized, and flickering (flickering) can be prevented. Therefore, it is possible to provide a projector device that can output a high-quality image without noise due to a speckle pattern and flickering of an image caused by the noise.
[0017]
Further, in the projector device of the present invention, not only the screen is provided as a separate body, but also a reflective screen that reflects and displays the output video, or an image display device, an image display device, and an image display device video. Also included is a projector device combined with a transmissive screen that transmits through. In particular, the rear type projector device employs a transmissive screen that has high directivity and easily recognizes speckle noise, and the image quality can be greatly improved by applying the present invention.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a rear projector 1 provided with an image quality improvement mechanism 40 of the present invention. In the rear projector 1 of this example, the display light (emitted light) 71 output from the projection lens system 30 forms an image on a transmissive screen (rear screen) 5, and the user 90 views the image through the screen 5. It is a device that can.
[0019]
The projector 1 of this example is configured such that a light source 20 that emits white light such as a white metal halide lamp in order from the light source 20 to the screen 5 and incident light 70 from the light source 20 from a host or control device (not shown). An image display device (LCD) 28 that outputs emitted light 71 that modulates based on a video signal and displays a desired image, and a lens system that projects (projects) the emitted light 71 emitted from the LCD 28 onto the screen 5. 30. Further, in the projector apparatus 1 of the present example, the image quality improvement mechanism so that the optical component 41 of the image improvement mechanism 40 crosses the optical path 72 through which the emitted light 71 passes on the screen 5 side (rear) in the vicinity of the projection lens system 30. 40 is arranged.
[0020]
The image improvement mechanism 40 uses a disk-shaped and transmissive optical component (optical element) 41, and a portion (optical surface) 42 that crosses the optical path 72 of the optical component 41 transmits the emitted light 71. At this time, processing is performed so that an optical path difference (phase difference) of about λ / 2 is generated depending on the location. Further, the image quality improvement mechanism 40 includes a driving unit 45 that rotationally drives the optical component 41. The driving means 45 of this example is attached to the rotation center of the optical component 41, and rotates a shaft 47 that is disposed substantially parallel to the optical axis 75 of the optical path 72 in the region that has passed through the lens system 30. A rotation motor 49 is provided, and the optical component 41 is moved in a direction orthogonal to the optical axis 75 by the driving means 45.
[0021]
An example of the optical component 41 of this example is schematically shown in FIG. 2, and a part thereof is enlarged and shown in FIG. The optical component 41 of this example is a transmissive substrate made of a transparent material such as glass that is substantially transparent as a whole and has the same refractive index, and the optical surface 42 has irregularities with a step of about 300 to 700 nm. It is formed by. The concave portion 43 and the convex portion 44 extend radially toward the outer periphery from the shaft hole 46 at the center of rotation with an order of width of at least about mm or more. The concave portions 43 and the convex portions 44 are alternately formed in the circumferential direction, and the disc-shaped optical surface 42 of the optical component 41 is equally divided in the circumferential direction by the concave portions 43 and the convex portions 44. Yes.
[0022]
The relationship between the step (depth) L due to the concave portion 43 and the convex portion 44 and the optical path difference Δ is given by the following equation (1).
[0023]
nL−L = Δ (1)
Therefore, when trying to set the wavelength so as to be approximately half the wavelength with respect to the light in the visible light region, the general light of glass is representative of the green light G (wavelength λG of about 550 nm) which is a wavelength near the center of the visible light region. If a high refractive index n (about 1.5) is used, the step L is about 550 nm. Further, red light and blue light can be calculated in the same manner. Therefore, by setting the step (depth) L due to the concave portion 43 and the convex portion 44 of the optical surface 42 of the optical component 41 to about 300 to 700 nm, the optical path difference of one wavelength or less around the half wavelength with respect to the light in the visible light region. Can be generated.
[0024]
In the projector device 1 of this example, the light beam of the emitted light 71 output from the projection lens system 30 passes (transmits) through the optical component 41 as indicated by the broken line A in FIG. To rotate in the direction of arrow B. Therefore, in the state shown in FIG. 2, the outgoing light 71 forms an image on the screen 5 through an optical path having an optical path difference of about half a wavelength on the right and left of the light beam, and the optical component 41 rotates due to the distribution of the optical path difference. So it varies with time. Since the speckle pattern generated on the screen 5 is a coherent pattern, it does not occur between lights having different half wavelengths, and in the state shown in FIG. 2, the screen passes through an optical path having an optical path difference of about the left and right half wavelengths. In the light imaged in FIG. 5, there is a high possibility that different speckle patterns are generated, and further, different speckle patterns are generated due to different wavelengths of light. Accordingly, a large number of speckle patterns are displayed on the screen by passing through the optical component 41 having a different optical path difference of about a half wavelength, and the speckle pattern varies with time when the optical component 41 is driven to rotate. For this reason, the intensity of one speckle pattern becomes very small, and further fluctuates with time, so that it is superimposed or time-integrated (time mixing) on the retina of the user 90 that recognizes the image displayed on the screen 5, Almost no pattern is recognized. As a result, the speckle pattern on the screen 5 cannot be individually recognized, and the speckle noise is not visible to the user 90.
[0025]
Although the diffraction phenomenon also occurs when the optical path difference is set by the optical component 41, the diffraction angle is very small by setting the distribution of the optical path difference, that is, the unevenness distribution in this example to the order of mm, for example, about 5 mm or more. Become. Therefore, it is possible to generate a large number of speckle patterns without affecting the imaging performance of the lens system 30 by providing irregularities of an appropriate size. It is possible to prevent the user from recognizing. Therefore, in the projector device 1 of this example, the speckle noise that can be seen on the screen 5 can be reduced by providing the image improvement mechanism 40. That is, the image of the present example is also applied to a compact high-resolution projector apparatus that has a small light source and is irradiated with coherent emission light 71 due to a miniaturized image display device. By providing the improvement mechanism 40, it is possible to reduce the substantial coherence of the outgoing light that has passed through the image quality improvement mechanism 40, and to reduce speckle noise, which is coherent noise. High quality video can be displayed on the screen 5 by exhibiting the above.
[0026]
Furthermore, the optical component 41 of this example is rotated at high speed by the drive means 45 so that the optical path difference can be changed at a cycle of about 24 to 30 Hz or more. By driving the optical component 41 at a speed higher than the speed at which humans can recognize individual pattern fluctuations, flickering of speckle patterns that fluctuate over time can be prevented. Therefore, a projector device that displays a high-quality image that does not show a speckle pattern, can prevent the influence of flicker by changing the speckle pattern over time, and has no adverse effect due to the rotation of the optical component 41. Can be provided.
[0027]
The increase in coherence due to the reduction in the size of the light source 20 is effective in reducing speckle noise even if the optical component 41 is arranged between the light source 20 and the image display device 28. However, the increase in speckle noise accompanying the miniaturization of the image display device 28 cannot be dealt with. On the other hand, in the projector apparatus 1 of the present example, as described above, the optical element 41 of the image quality improvement mechanism 40 is not on the optical path between the light source 20 and the LCD 28 that is an image display device, but from the LCD 28 to the screen. By arranging it on the optical path 72 leading to 5, speckle noise accompanying the occurrence of coherence of light due to the miniaturization of the LCD 28 can also be reduced. Therefore, the projector apparatus 1 has a configuration suitable for a projector apparatus that is further compact as a whole, and can provide a projector apparatus 1 that can project a compact, bright and high-resolution image.
[0028]
Furthermore, in this example, since the optical component 41 of the image quality improvement mechanism 40 is arranged behind the LCD 28 and on the screen 5 side of the lens system 30, the layout of the optical system from the light source 20 to the lens system 30 is not changed. An image quality improvement mechanism 40 can be incorporated. Therefore, speckle noise can be reduced very easily and image quality can be improved. Further, instead of incorporating the image quality improvement mechanism 40 into the projector apparatus 1, it is possible to add-on the optical system of the projector apparatus 1 as an option.
[0029]
In the above description, the step (depth) L due to the concave portion 43 and the convex portion 44 formed on the optical surface 42 of the optical component 41 is selected from a range of about 300 to 700 nm. Can be expressed by unevenness 43 and 44, and a plurality of optical path differences can be set on the optical path 71. In FIG. 2, a broken line (level) LR that can set an optical path difference of about half a wavelength of red light R, a step LG that can set an optical path difference of about a half wavelength of green light G, and a blue light An example is shown in which an LB that can set an optical path difference of about a half wavelength of B is formed. In this way, by providing an optical path difference of about half a wavelength at a wavelength corresponding to the three primary colors of light, it is possible to generate an infinite number of speckle patterns without color bias. Further suppression can be achieved.
[0030]
Further, the pattern formed for providing the optical path difference in the optical component 41 is not limited to that shown in FIG. In the optical component 41 shown in FIG. 4A, the concave portions 43 and the convex portions 44 are alternately arranged in the circumferential direction, and the concave portions 43 and the convex portions 44 are alternately arranged in the radial direction. Concave portions 43 and convex portions 44 are arranged in a shape. Therefore, the luminous flux of the emitted light 71 that traverses the optical component 41 is reversed not only on the left and right but also on the top and bottom, and more speckle patterns are formed on the screen 5. For this reason, the intensity of each speckle pattern is further reduced and the number of speckle patterns is increased, so that the speckle noise is easily whitened by mixing them with time.
[0031]
Furthermore, in the optical component 41 shown in FIG. 4B, the concave portion 43 and the convex portion 44 are formed almost randomly on the optical surface 42 thereof. Therefore, it is possible to project various speckle patterns on the screen at random timing, thereby eliminating regularity and further preventing the occurrence of flicker.
[0032]
Also, the optical component 41 shown in FIG. 4C is formed by alternately forming concave portions 43 and convex portions 44 at equal intervals (a constant pitch p) in parallel with the entire disk. Since all the concave portions 43 and the convex portions 44 can be formed in parallel, the optical component 41 can be easily manufactured, and the concave portions 43 and the convex portions 44 can be easily miniaturized. Considering the area where the luminous flux A of the emitted light 71 crosses, since the plurality of concave portions 43 and the concave portions 44 cross the area A, the number of speckle patterns increases, and furthermore, the concave portions 43 and the convex portions 44 according to the rotation of the optical component 41. Since the angle changes, regularity is also difficult to appear. Therefore, by setting the pitch p so as to be arranged, the same effect as in the above example can be obtained. Further, such an optical surface 42 can be easily molded. However, it can be said that the speckle noise is easily whitened and flicker is hardly generated.
[0033]
Furthermore, you may form by ion-doping the pattern similar to these uneven | corrugated patterns. By doping with appropriate ions, the refractive index of the glass substrate can be changed, and an optical path difference of about λ / 2 can be generated by the difference in refractive index. Then, by making the refractive index distribution as described above or other suitable pattern, it is possible to generate a large number of speckle patterns and mix them with time. In addition, plastic, birefringent optical material, or the like can be used instead of plate-like glass, and the same effect as described above can be obtained by creating an appropriate pattern that generates an optical path difference.
[0034]
FIG. 5 shows a projector device 2 different from the example shown in FIG. The projector apparatus 1 shown in FIG. 1 is a projector that employs a transmissive screen 5 known as a rear projector, and uses a highly directional screen such as a hologram screen. Therefore, when speckle noise is generated, it is easily recognized by the user's eyes 90. Therefore, the effect of providing the image quality improvement mechanism 40 is very large. On the other hand, the projector device 2 shown in FIG. 5 is a projector device 2 that projects an image on a reflective screen 6, and a light source 20, an LCD panel 28, The lens system 30 and the image quality improvement mechanism 40 are accommodated. Since this type of projector device 2 can separate the screen and other components, the projector can be miniaturized and has a configuration suitable for carrying. Even when the reflective screen 6 is used, the projector body 10 is further miniaturized and the LCD 28 is miniaturized, so that speckle noise is likely to occur.
[0035]
On the other hand, in the projector 2 of the present example, the optical component 41 of the image quality improvement mechanism 40 is installed between the lenses 31, 32, and 33 of the plurality of lenses 31, 32, and 33 that constitute the lens system 30, and the optical path difference The speckle noise is reduced by moving the optical surface 42 having the unevenness that generates the above. The image quality improvement mechanism 40 of this example employs a plate-like and substantially rectangular optical component 41 and reciprocates it with a linear motor 48 so that the speckle pattern can be mixed with time to be whitened. As the pattern for generating the optical path difference, it is possible to adopt an appropriate pattern such as a pattern in which irregularities are alternately arranged in a direction orthogonal to the driving direction, a random pattern as shown in FIG. Of course, an optical path difference may be provided depending on the difference in refractive index. Further, by driving the linear motor 48 to the millimeter unit or more, it is possible to prevent the optical component 41 from acting as a diffraction grating for separating the light flux.
[0036]
For this reason, the image quality improvement mechanism 40 of the linear drive system reciprocates the optical component 41, so it is necessary to sufficiently consider countermeasures such as vibration, but it is required to move the position of the optical component 41 with time. The space required for the projector 2 is small, so that the configuration is suitable for the compact projector 2.
[0037]
Further, in the projector device 2 of the present example, the optical component 41 is arranged at or near the position of the diaphragm in the lens system 30, thereby reducing the size of the optical component 41 and including the image quality improvement mechanism 40. Can be designed more compactly. That is, there is an aperture position in the projector lens system 30 where the cross-sectional area of the light beam becomes small. In many cases, an aperture is provided at that position to remove ambient light and improve image quality. Therefore, the optical component 41 can be miniaturized by arranging the optical component 41 at or near the aperture position, and the optical path difference can be set efficiently. On the other hand, since it is necessary to arrange a new optical component 41 in the lens system 30, a sufficient space is provided for arranging the optical component 41, and in the case of the zoom lens system 30, a position that does not affect zooming. It is necessary to arrange the optical component 41 on the surface. Therefore, although some time is required for the design, the projector 2 including the image quality improvement mechanism 40 can be summarized most compactly.
[0038]
FIG. 6 shows a further different projector device 3. In the above description, the projector apparatus having the image quality improvement mechanism 40 using the transmission type optical component 41 is described as an example. However, the image quality improvement mechanism 50 can be formed by the reflection type optical element (optical component) 51. It is. That is, in the projector apparatus 3 shown in FIG. 6, the mirror 51 that bends the direction of the outgoing light 71 by 90 degrees is disposed on the optical path 72 from the LCD 28 that is an image display device to the screen 6. A plurality of concave portions 53 and convex portions 54 for generating an optical path difference are formed by using the reflecting surface of the component 51 as an optical surface 52, and further, the mirror 51 is rotationally driven by a motor 49 which is a driving means 55 so that the optical path difference is temporally generated. The speckle noise can be whitened.
[0039]
As shown in FIG. 7, when the reflection surface is used as a surface that generates an optical path difference, the relationship between the uneven step L2 and the optical path difference Δ is expressed by the following equation (2).
[0040]
√2L = Δ (2)
Therefore, in order to generate an optical path difference Δ of about a half wavelength when the green light G having a wavelength λG of about 550 nm is reflected, it is desirable to provide a step L2 of 194 nm. Therefore, in order to provide an optical path difference of one wavelength or less in the visible light region, it is desirable to process the surface 52 of the mirror 51 by etching or the like so that the step L2 is about 200 nm.
[0041]
A pattern similar to that shown in each drawing of FIG. 2 or FIG. 4 can be adopted as the uneven pattern formed on the optical component 51 of the image quality improvement mechanism 50 of this example, and a transmission type optical component Similar to the image quality improvement mechanism employing the above, it is possible to whiten by generating an infinite number of speckle patterns and mixing them with time. Furthermore, the present invention is not limited to these patterns, and any pattern may be used as long as the optical path difference distribution varies at an appropriate frequency. At this time, as described above, since the diffraction angle becomes large and affects the image quality of the image when the pattern or the movement distance when driving the pattern becomes as fine as nm order, it is necessary to pay attention.
[0042]
In the above description, the single-plate projector (projection device) 10 is described as an example. However, the projector is not limited to this, and a three-plate projector may be used, and an optical path from the LCD, which is an image display device, to the screen. By providing the image quality improvement mechanism according to the present invention disclosed above, speckle noise can be reduced. In the image quality improvement mechanism, optical components that generate an optical path difference suitable for the wavelength of each color may be arranged behind the LCD that generates an image of each color, and may be temporally varied. Optical components that cover the whole may be installed on the optical path from the dichroic prism to the screen to reduce speckle noise.
[0043]
In the above description, the transmissive LCD 28 is described as an example of the video display system. However, the present invention is not limited to this, and other image display devices such as a reflective LCD or a micromirror device may be compact and high-powered. When the resolution is increased, miniaturization advances and the emitted light becomes coherent, and by applying the present invention, speckle noise can be reduced and a higher quality image can be displayed on the screen. it can.
[0044]
Further, in the above, a driving means for moving the optical component on the optical path is provided exclusively, but in a projector apparatus provided with a means for driving a rotary color filter, these driving means are also used. It is also possible to provide a simpler and more compact projector.
[0045]
In addition, the light source is not limited to the metal halide lamp 20 shown above, but a xenon lamp or a high-pressure mercury lamp that emits white light may be used, and a light source having a high coherence such as a laser or LED may be used. Even in this case, the same effect can be obtained.
[0046]
【The invention's effect】
As described above, according to the present invention, an image quality improvement mechanism that moves an optical component that gives a slight optical path difference to emitted light on the optical path from the image display device to the screen to temporally vary the optical path difference distribution. By providing, various speckle patterns are generated, and the speckle noise visible on the screen can be reduced by integrating them with time. Furthermore, in the present invention, the image display device is miniaturized in addition to the coherence due to the miniaturization of the light source by being arranged on the optical path of the emitted light behind the image display device such as an LCD. Speckle noise accompanying an increase in coherence of light caused by the above can be reduced. Therefore, it is possible to provide a projector device that can project a bright and beautiful high-resolution image on a screen while being compact.
[Brief description of the drawings]
FIG. 1 is a diagram showing an outline of a rear type projector apparatus using a projector provided with an image quality improvement mechanism of the present invention.
2 is a diagram showing an outline of a pattern formed on an optical component of the image quality improvement mechanism shown in FIG.
FIG. 3 is an enlarged view showing a part of the pattern of the optical component shown in FIG. 2;
4 is a diagram showing some examples of patterns different from the uneven pattern shown in FIG. 2; FIG.
FIG. 5 is a diagram showing an outline of a projector device different from the projector device shown in FIG. 1;
FIG. 6 is a diagram showing an outline of a different projector device.
7 is an enlarged view showing a part of the pattern of the reflective optical component shown in FIG. 6;
[Explanation of symbols]
1, 2, 3 Projector device
5 Transmission screen (rear screen)
6 Reflective screen
10 Housing (Projector body)
20 Light source
28 Image display device (light valve, LCD)
30 Lens system
40, 50 Image quality improvement mechanism
41, 51 Optical components
42, 52 Optical surface
43, 53 recess
44, 54 Convex
45, 55 Drive means
48, 49 Motor
70 Incident light
71 Outgoing light
72 On the light path
75 optical axis
90 users

Claims (16)

A light source;
An image display device capable of modulating light from the light source;
A lens system that projects light from the image display device onto a screen;
An optical component for generating an optical path difference distribution to the extent that the light beam is arranged in the aperture position or near the squeezed, does not affect the image displayed on the screen of the optical path to the screen from the image display device,
And a drive unit that moves the optical component so that the optical path difference distribution varies with time. According to claim 1, wherein the optical component, the light beams reaching the screen from the image display device transmitted or reflected, and a portion for generating an optical path difference of one wavelength about or less with respect to light in the visible light region Projector device.   The projector device according to claim 2, wherein the portion of the optical component that generates the optical path difference is provided with unevenness that generates a level difference of about the wavelength of light in the visible light region or less.   3. The projector device according to claim 2, wherein regions of the optical component that generate the optical path difference are distributed in regions having different refractive indexes so as to generate an optical path difference that is about the wavelength of light in the visible light region or less.   The projector device according to claim 1, wherein the driving unit rotationally drives the optical component.   The projector device according to claim 1, wherein the driving unit reciprocates the optical component.   The projector device according to claim 1, wherein the driving unit moves the optical component at about 24 to 30 Hz or at a higher speed.   The projector device according to claim 1, wherein the optical component is disposed on the screen side of the lens system.   The projector device according to claim 1, wherein the optical component is disposed inside the lens system.   The projector device according to claim 1, comprising the reflective or transmissive screen. Modulating light from a light source in an image display device, the aperture at or near the light beam is squeezed in an optical path from the image display device on the screen of the projector apparatus for projecting on a screen via the lens system the light Optical components that are arranged and generate an optical path difference distribution that does not affect the image displayed on the screen;
An image quality improvement mechanism having drive means for moving the optical component so that the optical path difference distribution varies with time. According to claim 11, wherein the optical component, the light beams reaching the screen from the image display device transmitted or reflected, and a portion for generating an optical path difference of one wavelength about or less with respect to light in the visible light region Image quality improvement mechanism. 13. The image quality improvement mechanism according to claim 12 , wherein the portion of the optical component that generates the optical path difference includes unevenness that generates a level difference of about the wavelength of light in the visible light region or less. 13. The image quality improvement mechanism according to claim 12 , wherein the portion of the optical component that generates the optical path difference is distributed in regions having different refractive indexes so as to generate an optical path difference that is about the wavelength of light in the visible light region or less. . 12. The image quality improvement mechanism according to claim 11 , wherein the driving means rotates or reciprocates the optical component. 12. The image quality improvement mechanism according to claim 11 , wherein the driving unit moves the optical component at about 24 to 30 Hz or faster.

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