JP2013025052A - Iris plane spatial imaging control-type image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device having a narrow viewing angle, which eliminates loss of energy resulting from an unnecessarily wide viewing angle, contributing to energy conservation.SOLUTION: A fundamental imaging system includes three planes composed of an object plane, an imaging plane, and a lens plane. A lens 8 having a focal length f1 approximately equal to a distance "a" between the object plane and the lens plane is arranged in the object plane located in the output plane of a homogenizer 4 for achieving at least angularly uniform light intensity. Transmissive optical modulation means 12 having low light diffusion capability is disposed in the lens plane of a lens 10 having a focal length f2 or in the vicinity thereof. The imaging plane is positioned at a position away from the lens plane by a distance "b" which satisfies the following equation:(1/a)+(1/b)=1/f2.

Description

  The present invention can send an image only to a limited narrow area of an image viewing position of an observer, and can save energy by avoiding wasteful power consumption due to sending an image outside that area. The present invention relates to an iris surface space imaging control type image display device.

  Various display devices generally allow a single display image to be viewed by many observers positioned at different angles with respect to the display screen. In other words, the basic design concept is to have a relatively wide viewing angle with high resolution and good contract, and many of them use diffusion means (for example, a diffusion film) to realize the wide viewing angle.

  Japanese Unexamined Patent Publication No. 2007-183498 (Patent Document 1) introduces such a diffusion film and projection system, and FIG. 5 shows an example of such a diffusion film. In FIGS. 4A to 4C, light incident on one lens (incident side lens) at the same angle is condensed at a position corresponding to the angle, and the light condensed at each position is This shows the principle of diffusion in a certain angle range by another lens (outgoing side lens) arranged at the focal position of the lens. (D) is sectional drawing of the diffusion film which integrated the said two lenses.

By making full use of such a diffusion film, the light constituting the image condensed at a position corresponding to the incident angle can be diffused in a certain range of the exit side lens by the action of the entrance side lens. All the observers located in the diffusion angle range can be made to visually recognize the image.
Therefore, a display device using such a diffusion film for widening the viewing angle can be viewed over a wide range of angles by appropriately setting the diffusion angle, thereby realizing a wide viewing angle. Can do.

JP 2007-183498 A

By the way, not all display devices are required to have a wide viewing angle. In other words, there may be a narrow viewing angle.
For example, a television display provided for each passenger seat such as a passenger plane, or a display such as a personal television, a personal computer, a mobile phone, or a portable information terminal.

These displays are basically only viewed by one person and can only be seen by that person. In extreme terms, it can be said that it is only necessary to send image light only to a narrow region where both eyes of the human being exist.
However, even such a display with a narrow viewing angle usually has a viewing angle that is considerably wider than the minimum required viewing angle. Conventionally, technology development for widening the viewing angle has been actively conducted. However, there has been no technical development to narrow the viewing angle so as not to unnecessarily widen the viewing angle.

This is because there was no recognition in the field of display device development that widening the viewing angle more than necessary resulted in unnecessary power consumption and contrary to the spirit of energy saving.
If the display device originally has a wider viewing angle than the viewing angle required for the display device, an image is output in vain due to the wider viewing angle.
For example, if it is sufficient that an image can be output to both eyes of a single human being, but it has a characteristic of outputting an image to an area that can be simultaneously viewed by several to tens to hundreds of people, that number Image output to an area where people, dozens or hundreds minus one person can visually recognize is completely useless. This naturally creates a waste of light and the like that is generated for displaying an image, and thus a waste of energy consumed.

Many engineers are unaware of the existence of such waste, but the inventor of the present application has implemented a planned power outage due to the Fukushima nuclear accident caused by the Great East Japan Earthquake, legalization of power saving to large companies, small companies, general households As a result of such a demand for power saving, the use of a display device with an unnecessarily wide viewing angle has led to the recognition of wasteful power consumption and the need to eliminate such waste.
And this inventor thought to eliminate the waste, repeated experiment, and came to make this invention.
That is, an object of the present invention is to provide a display device with a narrow viewing angle, thereby eliminating energy waste due to having a wider viewing angle than necessary and contributing to energy saving.

An iris surface space imaging control type image display device according to claim 1 comprises a basic imaging system having three surfaces, an object surface, a lens surface, and an imaging surface, and the object surface is angularly or angularly An output surface of a homogenizer that realizes substantially uniform light intensity both spatially and spatially, and a lens that is located on the output surface and has a focal length f1 that is substantially equal to the distance a between the object surface and the lens surface. A transmissive light modulation means having little or no light diffusibility is arranged at or near the lens surface of the lens having the focal length f2 of the surface, and the imaging surface is located at a distance b satisfying the following equation from the lens surface. It is characterized by being located.
Equation: (1 / a) + (1 / b) = 1 / f2

The iris surface space imaging control type image display device according to claim 2 comprises a basic imaging system having three surfaces of an object surface, a lens surface, and an imaging surface. Output surface of a homogenizer that realizes substantially uniform light intensity both spatially and spatially, and a lens having a focal length f1 located on the output surface is disposed, and a non-axial aspheric Fresnel reflection of the focal length f2 of the lens surface A transmissive light modulation means having little or no light diffusibility is arranged in the lens surface of the mirror or in the vicinity of the front side thereof, the imaging surface is located at a distance b away from the lens surface, and the object surface to the lens surface The distance is a which is substantially equal to the focal length f1 of the lens, and the following equation is substantially established between the a and b and the focal length f2.
Equation: (1 / a) + (1 / b) = 1 / f2

An iris surface space imaging control type image display device according to claim 3 is the iris surface space imaging control type image display device according to claim 1 or 2, wherein the internal refractive index distribution has a top hat diffusion characteristic independent of an incident angle. A homogenizer is formed by stacking one or a plurality of diffusion films of a mold.
The iris surface space imaging control type image display device according to claim 4 is the iris surface space imaging control type image display device according to claim 1, 2 or 3, wherein two fly-eye lenses or lenticular lenses 2 are used as the homogenizer. Two sets of lenses in which a pair of lenses are placed apart from each other by the focal length of the lenses are used orthogonal to each other.

The iris surface space imaging control type image display device according to claim 5 is the iris surface space imaging control type image display device according to claim 1, 2, 3 or 4, wherein the lens having the focal length f1 is within an effective diameter. A plurality of homogenizer output surfaces are arranged in an array (one-dimensional or two-dimensional).
The iris surface space imaging control type image display device according to claim 6 is the iris surface space imaging control type image display device according to claim 1, wherein the transmission type light modulating means is the lens surface. To the object plane side at a distance within the lens focal length f2.

According to the iris surface space imaging control type image display device of the first aspect, since the transmissive light modulation means is not used which has the diffusion characteristic, the diffusion of the image light is suppressed and the viewing angle is narrowed. Is possible.
Depending on the embodiment, the viewing angle can be reduced to one-hundredth, one-thousandth, even one-thousandth, or even one-hundred-thousandth of a solid angle. Can contribute.
Further, since the light is not diffused, the external light can be passed through without being diffused, and the adverse effect due to the external light can be remarkably reduced.

According to the iris surface space imaging control type image display device of claim 2, since the non-axial aspheric Fresnel reflector is used as the lens surface, the light from the object surface is converted into the lens of the non-axial aspheric Fresnel reflector. It is possible to irradiate the surface obliquely from the front side, modulate the light by the light modulation means on the front side of the lens surface, and form an image on the iris surface.
Accordingly, it is possible to provide a front type iris surface space imaging control type image display device. Of course, the fact that the viewing angle can be narrowed and the adverse effects of external light can be remarkably reduced is the same as in the iris surface space imaging control type image display device of claim 1.

According to the image display device of the iris surface space imaging control type according to claim 3, the rod-like integrator is obtained by using an internal refractive index distribution type diffusion film having a top hat diffusion characteristic independent of an incident angle as a homogenizer. Even if not used, the light intensity can be substantially uniform both angularly and spatially, and the homogenizer can be easily downsized.
According to the iris surface space imaging control type image display device according to claim 4, two sets of lenses each having two fly-eye lenses or two lenticular lenses as a homogenizer and spaced apart from each other by the focal length of the lens are mutually connected. Since the orthogonal ones are used, the light intensity can be made uniform in angle, the light intensity can be made uniform in angle, and the deterioration of the image quality that the peripheral part of the screen becomes darker than the central part is avoided. Can do.

According to the iris surface space imaging control type image display device according to claim 5, in the iris surface space imaging control type image display device according to 1, 2, 3 or 4, the effective diameter of the lens having the focal length f1 is within the effective diameter. In addition, since the plurality of homogenizer output surfaces are arranged in an array (one-dimensional or two-dimensional), it is possible to set a plurality of positions for imaging in space.
The position of the observer is detected by a known technique related to face recognition systems and eye tracking that are prevalent in the field of digital cameras and the like, and only the light source corresponding to the detected observer is turned on (lights on). Thus, although an image is displayed in a necessary area, an image is not displayed in an area where there is no observer and therefore an image display is not necessary.
Therefore, it is possible to increase the area where image display is possible and to avoid wasting energy used for image display.

  According to the iris surface space imaging control type image display device of the sixth aspect, since the transmission type light modulation means is located at a position shifted from the lens surface to the object plane side within the focal length f2 of the lens, the observer side From the above, a virtual image by the transmissive light modulating means can be enlarged and viewed by a lens (lens having a focal length f2).

1 is a perspective view showing a first embodiment of an iris surface space imaging control type image display device according to the present invention; FIG. It is explanatory drawing of the energy-saving effect of the Example of FIG. It is a perspective view which shows the 2nd Example of the iris surface space imaging control type image display apparatus of this invention. It is a perspective view which shows the 3rd Example of the iris surface space imaging control type image display apparatus of this invention. An example of the diffusion film introduced by patent document 1 which is the technique which conventionally used the diffusion means (for example, diffusion film) for realization of a wide viewing angle is shown. In FIGS. 4A to 4C, light incident on one lens (incident side lens) at the same angle is condensed at a position corresponding to the angle, and the light condensed at each position is This shows the principle of diffusion in a certain angle range by another lens (outgoing side lens) arranged at the focal position of the lens. (D) is sectional drawing of the diffusion film which integrated the said two lenses.

The first one of the iris surface space imaging control type image display device according to the present invention basically has an angle on the object plane of the basic imaging system having three surfaces of an object plane, an imaging plane, and a lens plane. Or a homogenizer output surface that realizes substantially uniform light intensity angularly and spatially, and a lens that is located on the output surface and has a focal length f1 that is approximately equal to the distance a between the object surface and the lens surface. A transmission type light modulator having no or little light diffusing characteristic is disposed on or near the lens surface of the lens having the focal length f2 of the lens surface, and is spaced from the lens surface by a distance b satisfying the following equation: The imaging plane is positioned. Equation: (1 / a) + (1 / b) = 1 / f2
The first iris surface space imaging control type image display device of the present invention is a rear type image display device, while the second iris surface space imaging control type image display device of the present invention is A non-axial aspherical Fresnel reflector is used as a lens surface, and the transmissive light modulation means is arranged on the front side of the lens surface, so that light from the object surface is aspherical aspherical Fresnel with the lens surface. The reflecting mirror can be irradiated from an oblique front side, and thus is a front type.
Furthermore, a reflection means is added, and the light from the object plane is not directly irradiated to the non-axial aspherical Fresnel reflector having the lens surface, but the light from the object plane is reflected by the added reflection means to be non-axial. An aspheric Fresnel reflector may be irradiated.

A preferred example of the transmission type light modulating means of the iris surface space imaging control type image display device of the present invention is a liquid crystal panel having no light diffusing means without a backlight.
Liquid crystal panels and the like are usually colored by color filters, but are equipped with light source chips of three colors R (red), G (green), and B (blue) as light sources. The emission color can be switched, and the illumination light can be given to the transmissive light modulation means such as a liquid crystal panel in a color sequential manner. If the switching of the emission color of the light source and the switching of the image modulation target color of the light modulation means are performed in synchronization, a light modulation means such as a liquid crystal panel without a color filter can be used.

Further, a rod-like integrator (light pipe) is suitable as a homogenizer of an iris surface space imaging control type image display device, but the rod-like integrator is merely an example of a homogenizer.
In addition, as a homogenizer, a pair of lenses in which two fly-eye lenses or two lenticular lenses are set apart from each other by the focal length of the lenses may be used in an orthogonal manner. In such a case, the angular uniformity can be made extremely high, and the image quality can be further improved.

In addition, if a homogenizer is used in which one or a plurality of internally refracting diffusion films having top hat diffusion characteristics independent of the incident angle are used, the angular and spatial characteristics can be obtained without using a rod-like integrator. In particular, a substantially uniform light intensity can be obtained, and the homogenizer can be easily downsized.
Also, the output surfaces of a plurality of homogenizers can be arranged in an array (one-dimensional or two-dimensional) within the effective diameter of the lens at the focal length f1. By doing in this way, the position imaged in space can be made into multiple places.

And by using eye tracking technology that detects the presence of the eyes already used in digital cameras, only the light source corresponding to the area where the presence of the eye is detected is turned on, and the area where the eye is absent is supported. The light source to be turned off can be turned off. Thereby, a further energy saving effect can be obtained.
Further, when a liquid crystal panel having no light diffusing means without a backlight is used as the transmissive light modulating means described above, the liquid crystal panel is moved from the lens surface to the object plane side within the focal length f2 of the lens. When arranged at a distance, the virtual image of the liquid crystal panel can be enlarged and viewed from the viewer side.
Thus, the present invention can be implemented in various modes, and there can be various modifications.

(First embodiment)
FIG. 1 is a perspective view showing a first embodiment of an iris surface space imaging control type image display device according to the present invention.
In the figure, reference numeral 2 denotes a light source, and an LED (light emitting diode) is used in this example. Reference numeral 4 denotes a homogenizer that receives light from the light source 2 on its incident surface, and a rod-like integrator is used in this example. This homogenizer 4 makes the intensity of light from the light source 2 spatially uniform and emits it from the output surface.
As the homogenizer, two sets of lenses in which two fly-eye lenses or two lenticular lenses are placed apart from each other by the focal length of the lenses may be used.
A diffusion film 6 is disposed on the output surface side of the homogenizer 4 and plays a role of making the angle uniform.

In this example, the diffusion film 6 is a laminate of Diffuse Light Control-film (DLC-film) developed by the present applicant (National Tohoku University) so that the diffusion directions are perpendicular to each other. It is what.
The laminated D.D. L. C. -Film has a top hat-like uniform diffusion characteristic independent of the incident angle, and thus can serve as an angularly uniform homogenizer. Accordingly, uniform light is emitted from the output surface of the diffusion film 6 both spatially and angularly.

Reference numeral 8 denotes a lens provided in the vicinity of the output surface of the diffusion film 6, and its focal length is f1. Due to the action of the lens 8, the angular information and the spatial position information are exchanged on the surface that is away from the lens 8 toward the emission side by the focal length f 1 (= a), and light that is uniform both spatially and angularly. The surface is enlarged and irradiated.
Reference numeral 10 denotes a Fresnel lens disposed at the above-mentioned position shifted from the lens 8 by the focal length f1 (= a) to the emission side, and the focal length is f2. Reference numeral 12 denotes a transmissive light modulation means disposed in the vicinity of the exit surface of the Fresnel lens 10. In this example, a liquid crystal panel (LCD panel) having no backlight and having no light diffusion characteristics is used. Yes.

Since the Fresnel lens 10 and the light modulation means 12 are arranged at the position away from the lens 8 by the focal length f1 (= a), as described above, both in terms of the angle incident on the Fresnel lens 8 and spatially. The light that has been made uniform is modulated by the light modulation means 12 on the surface thereof, and is moved from the light modulation means 12 to the emission side by a distance b that satisfies the condition of (1 / a) + (1 / b) = 1 / f2. A surface 14 is formed at a distance.
This surface 14 is in a conjugate relationship with the exit surface of the diffusion film 6 provided on the exit surface of the homogenizer 4, and is therefore a surface that is uniform both spatially and angularly. Therefore, in the present specification, the surface 14 is referred to as a spatial imaging iris surface.

When a human eye is placed in the spatial imaging iris surface 14, image information, which is angle information of the eye lens, is imaged on the retina as position information, so that a spatially uniform image can be viewed. become.
Furthermore, even if the eye is moved within the spatial imaging iris plane 14, the spatial uniformity is realized within the iris plane 14, so the brightness of the entire image being viewed is also constant.

According to such an iris surface space imaging control type image display device, since the liquid crystal panel (LCD panel) having no backlight and having no light diffusion characteristics is used as the light modulation means, the image light is not diffused. . Therefore, the viewing angle can be remarkably narrowed, and the energy saving effect can be obtained.
FIG. 2 is an explanatory diagram of the energy saving effect. In the figure, the energy saving effect is S2 / S1, and S2 / S1 is expressed by the following equation. Note that S1 is a solid angle at which light from a device having normal light diffusion characteristics diffuses, S2 is a solid angle at which light from the device of this embodiment is diffused, and r is the distance from the eye to the screen.

S2 / S1 = π (r · tan θ) 2 / (2πr 2) = (tan θ) 2
Since a person has both eyes, the energy saving effect = 2 × (tan θ) 2/2 = (tan θ) 2.
Now, assuming that the diameter of the spatial imaging iris surface is 6 cm at a position 3 m away, tan θ = 3 cm / 3 m = 1/100, so energy saving effect = (tan θ) 2 = 1/10000, which is more than 1/10000 Low power consumption is established for one person. Even if 10 people are watching, 1/1000 of ultra-low power consumption is realized. Considering that the power consumption of the backlight of the liquid crystal panel accounts for 90% to 95% of the power consumption of the entire liquid crystal panel, the effect of the above technique is great.

(Modification 1)
In the first embodiment, the transmissive light modulating means, for example, the liquid crystal panel 12 having no backlight and having no diffusing characteristic is not located close to the lens 10 but from the lens 10 to the object surface side, that is, the lens 8. Alternatively, the lens 10 may be disposed at a position separated by a distance within the focal length f2 of the lens 10.
In this way, from the observer side, the virtual image by the transmissive light modulation means 12 can be enlarged and visually recognized by the lens (lens having the focal length f2).

(Modification 2)
Further, as the light source 2, an RGB sequential light source that incorporates three light emitting means for emitting R (red), G (green), and B (blue) and can switch the light emitting means in a predetermined order. If used, a color iris surface space imaging control type image display device can be realized even if a monochrome image modulation means is used.
That is, the color of light emitted from the RGB sequential light source 2 every 1/180 seconds obtained by dividing 60 seconds into three equal parts is, for example, red (R), green (G), blue (B), red (R), green ( G), blue (B),... In synchronization therewith, the color components of the image information of the transmissive light modulator 12 are red (R), green (G), blue (B), red (R), green (G), blue (B),. -Switch in the order. As a result, a color iris surface space image formation control type image display device can be realized even when a monochrome image modulation means is used.

(Second embodiment)
FIG. 3 is a perspective view showing a second embodiment of the iris surface space imaging control type image display device according to the present invention. This embodiment is different from the first embodiment shown in FIG. Although different in that each is formed into an array by providing a plurality of generators 4, it is common in other points.
In this embodiment, the light source 2 and the homogenizer 4 are arrayed when there are a plurality of observers or when one or a few observers can change the position of the eyes. The image is generated only on the iris surface 14 in the area where the eye (the eye) exists, and the image is not displayed in the area where the observer (the eye) does not exist, so that the energy consumed for the image display is not wasted. It is for doing so.

In the drawing, 2a is a light source array in which a large number of light sources 2, 2,... Are arranged in an array, and 4a is a homoge provided corresponding to each light source 2, 2,. Is a homogenizer array composed of the nizers 4, 4,..., Each of the homogenizers 4, 4,. Exit. A diffusion film 6 is disposed on the exit surface of the homogenizer array 4, and light having a uniform intensity distribution is emitted from the output surface both spatially and angularly, as in the first embodiment. .
Reference numeral 8 denotes a lens provided in the vicinity of the output surface of the diffusion film 6, and its focal length is f1. A Fresnel lens 10 (having a focal length f2) is disposed at a distance a equal to the focal length f1 from the lens 8, and light modulation means (for example, there is no backlight, close to the Fresnel lens 10) A liquid crystal panel 12 having no diffusion characteristics is disposed.

According to such an embodiment, from the position where the Fresnel lens 10 and the light modulation means 12 are arranged close to each other, on the distance b emission side satisfying the equation (1 / a) + (1 / b) = 1 / f2. The light emitted from the light sources 2, 2,... Of the light source array 2a and incident on the homogenizers 4, 4,. .. Are formed in an array. Reference numeral 14a denotes an iris surface array.
And, by detecting the position of the observer by a known technique related to the face recognition system and eye tracking popular in the camera technology, by turning on (lighting up) only the light source 2 corresponding to the detected observer, Although an image is displayed in a necessary area, there is no observer, and therefore an image can be prevented from being displayed in an area that does not require image display.
Therefore, it is possible to prevent waste of energy consumed for image display.
In this example, the light sources 2, 2,... And the homogenizers 4, 4,... Are arranged in a two-dimensional array, but may be arranged in a one-dimensional array. .

(Third embodiment)
FIG. 4 is a perspective view showing a third embodiment of the iris surface space imaging control type image display device of the present invention.
In this embodiment, the rear type iris surface space imaging control type image display device shown in FIG. 3 is modified to a front type image display device. Can be achieved.
This embodiment is different from the embodiment shown in FIG. 3 in that a means necessary for making the front type is taken, but is common in other points.

  In the figure, 2a is a light source array comprising a plurality of light sources 2, 2,..., 4a is a homogenizer 4, 4,. Is a homogenizer array. A diffusion film 6 is the same as the diffusion film of the first and second embodiments, for example, and has a top-hat-like uniform diffusion characteristic of the light from the homogenizer array 4a independent of the incident angle. . Therefore, light having uniform light intensity is emitted from the emission surface of the diffusion film 6 both spatially and angularly.

Reference numeral 16 denotes a lens disposed close to the exit surface of the diffusing film 6 and plays a role corresponding to the lens 8 of the second embodiment or the first embodiment. In this example, an aspherical and non-axial lens is used. It is used. The focal length of this lens 16 is f1.
Reference numeral 18 denotes an aspherical aspherical mirror that reflects the light from the lens 16. In this example, an aspherical aspherical mirror is provided, which plays a role in changing the display device from the rear type to the front type. Fulfill.
Reference numeral 10r denotes an axisymmetric aspheric Fresnel reflector, which plays a role corresponding to the Fresnel lens 10 of the first and second embodiments, but does not have transparency and has reflectivity. This is different from the Fresnel lens 10 of the second embodiment.

Reference numeral 12 denotes light modulation means, which is disposed close to the front (observer side) of the non-axis aspheric Fresnel reflector 10r, and modulates the light reflected by the reflector 10r.
The optical modulation means 12 and the non-axial aspherical Fresnel reflecting mirror 10r arranged in proximity to each other have an optical path length that reaches the lenses 12, 10r from the lens 16 through the mirror 18 to the same distance a as the focal length f1 of the lens 16. It is arranged.
Then, the light source is located at a position spaced from the light modulation means 12 and the non-axis aspheric Fresnel reflector 10r toward the light exit side by the distance b exit side satisfying the equation (1 / a) + (1 / b) = 1 / f2. Are emitted from the light sources 2, 2,... Of the array 2a and are incident on the homogenizers 4, 4,. Are formed in an array.

In this way, the light source array 2a and the homogenizer array 4a can be placed closer to the observer than the light modulation means 12 and the non-axial aspheric Fresnel reflector 10r, and thus the iris surface space imaging control type. The image display device can be reduced in thickness and size.
In this embodiment, the light source 2 and the homogenizer 4 are arrayed in the front type, but the light source 2 and the homogenizer 4 are arrayed as in the first embodiment. The present invention can also be implemented in an embodiment in which a rear type image display device that does not become a front type is made a front type.

  According to the present invention, an image can be sent only to a limited narrow area called an image viewing position of an observer, and energy is saved by avoiding unnecessary power consumption caused by sending an image outside the area. It can be widely applied to an iris surface space imaging control type image display device, and can be applied not only to a rear type image display device but also to a front type image display device. .

2 ... light source, 2a ... light source array, 4 ... homogenizer,
4a ... homogenizer array, 6 ... diffusion film,
8: Lens (focal length f1),
10 ... Fresnel lens, 10r ... non-axial aspherical Fresnel reflector 12 ... light modulating means (light diffusing means having no backlight and no diffusion characteristics),
14 ... Iris surface, 14a ... Iris surface array, 16 ... Lens,
18: Reflecting means.

Claims (6)

It consists of a basic imaging system that has three surfaces: an object plane, a lens plane, and an imaging plane.
The object plane is positioned on the output surface of the homogenizer that realizes substantially uniform light intensity angularly or angularly and spatially, and is approximately equal to the distance a between the object plane and the lens surface. A lens having a focal length f1 is disposed;
A transmissive light modulation means having little or no light diffusivity is disposed on or near the lens surface of the lens having the focal length f2 of the lens surface,
An iris surface space imaging control type image display device, wherein the imaging surface is located at a position separated from the lens surface by a distance b satisfying the following equation:
Equation: (1 / a) + (1 / b) = 1 / f2 A homogenizer comprising a basic imaging system having three surfaces, an object surface, a lens surface, and an imaging surface, which realizes substantially uniform light intensity angularly or angularly and spatially on the object surface. And an output surface and a lens located on the output surface and having a focal length f1,
A transmissive light modulation means having little or no light diffusivity is disposed on the lens surface of the non-axis aspherical Fresnel reflector having the focal length f2 of the lens surface or in the vicinity of the front surface thereof, and is connected to a position separated from the lens surface by a distance b. The image plane is located,
The distance from the object surface to the lens surface is a, which is substantially equal to the focal length f1 of the lens, and the following equation is substantially established between the a, b and the focal length f2. Iris surface spatial imaging control type image display device.
Equation: (1 / a) + (1 / b) = 1 / f2 In the iris surface space imaging control type image display device according to claim 1 or 2,
An iris surface space imaging control type image display device characterized in that a homogenizer is formed by superposing one or a plurality of internal refractive index distribution type diffusion films having a top hat diffusion characteristic independent of an incident angle. In the iris surface space imaging control type image display device according to claim 1, 2, or 3,
Iris surface spatial imaging characterized in that two sets of lenses in which two fly-eye lenses or two lenticular lenses are separated from each other by the focal length of the lenses are orthogonal to each other as the homogenizer Control type image display device. In the iris surface space imaging control type image display device according to claim 1, 2, 3, or 4,
Iris surface spatial imaging control type image display device, wherein a plurality of homogenizer output surfaces are arranged in an array (one-dimensional or two-dimensional) within the effective diameter of the lens having the focal length f1 . In the iris surface space imaging control type image display device according to claim 1, 3, 4, or 5,
An iris surface space imaging control type image display device, wherein the transmission type light modulation means is disposed at a distance within the lens focal length f2 from the lens surface to the object surface side.

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