JP2990580B2 - Image output device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention relates to small objects, documents,
Negative and reversal photographic films, photographic print, captures image information such as the exposure mask pattern, to images output device you output <br/> it. The output here refers to a case in which an image for visual observation is directly displayed on a screen or the like as a display device, or an image is output on some medium such as photographic paper or photographic film in order to take a hard copy. This includes the case where image information is transmitted and printed as an input signal to an image processing device / measurement device or the like connected to the output side.

[0002]

2. Description of the Related Art In order to obtain a magnified and projected high-brightness display, a target image is once input to a spatial light modulator, and the image is read out using a powerful light source. There is a device for displaying an image, and in particular, a device using an optical writing type liquid crystal spatial light modulator is commercially available. A conventional example of an apparatus for displaying an output target image using such a spatial light modulator will be described with reference to FIG.

FIG. 6 shows an example of the basic configuration of an image output device using the above spatial light modulator. First, a configuration of an input optical system for forming an output target image of the present apparatus on a writing surface of a spatial light modulator will be described. In FIG. 6, an input optical system includes a writing light source 151, a parallel optical system 152 (here, a combination of an elliptical mirror and a collimator lens) for making light from the writing light source 151 parallel and uniform light intensity, and a parallel optical system. An input image medium 150 that forms a light beam of an input image by a light beam from a writing light source 151 via a system 152, and an input imaging system 102 that forms the light beam of the input image on a writing surface of the spatial light modulator 103 It consists of. Here, the operation of the input optical system will be described with reference to the drawings.

The writing light from the writing light source 151 is converted by the parallel optical system 152 into a substantially parallel light beam having a uniform light intensity.
The light enters the input image medium 150. The writing light incident on the input image medium 150 forms an input image by transmitting through the input image medium 150, and forms an image on the writing surface of the spatial light modulator 103 via the input imaging system 102. Thus, the input image is written on the writing surface of the spatial light modulator 103. The input image thus written is subjected to a desired light modulation by the spatial light modulator 103 and appears on the reading surface. At this time, the light modulation performed by the spatial light modulator 103 is performed by the driving circuit 104.
Is controlled by

Next, a description will be given of a configuration of an output optical system for reading an image to be output by the present apparatus from the reading surface of the spatial light modulator and finally forming an image on the output image surface. In FIG. 6, the output optical system includes a reading light source 153 and a parallel optical system 15 for making the light from the reading light source 153 parallel and making the light intensity uniform.
4 (here, a combination of an elliptical mirror and a collimator lens), a polarizing beam splitter 155 (hereinafter, referred to as PBS) for irradiating the reading surface of the spatial light modulator 103 with the light beam of the reading light source 153 via the parallel optical system 154, An output imaging system 170 for imaging the light flux of the output image on the output image plane 156
It consists of.

For an image output apparatus having the above-described configuration, which aims at optical amplification, a light source having a very high light intensity is used as a reading light source. Here, the operation of the output optical system will be described with reference to the drawings. The reading light from the reading light source 153 is converted into a substantially parallel light beam having a uniform light intensity by the parallel optical system 154, and is incident on the PBS 155. PBS 155
The readout light incident on the light is split into P-polarized light and S-polarized light, and the S-polarized light is reflected by the reflection surface of the PBS 155 and irradiates the readout surface of the spatial light modulator 103. This spatial light modulator 103
Of light irradiating the readout surface are phase-modulated and reflected on the readout surface. In this way, the image information of the read light is converted from phase modulation to intensity modulation by transmitting through the PBS 155 again. The image information of the intensity-modulated light is output by the output imaging system 170 to the output image plane 15.
6 is formed.

The configuration of a conventional holder unit in the above-described image output apparatus will be described with reference to FIGS. The spatial light modulator 103 is accommodated in a central portion of the holder 201 via a writing mask 202 on the writing surface side and a reading mask 204 on the reading surface side. Then, a holder cover 301 having an opening that is sufficiently larger than the opening of the reading mask 204 is fixed to the holder 201 to form a holder unit. When the holder unit is actually incorporated into the optical system, as described above with reference to FIG. 6 as an example, the temperature of the spatial light modulator 103 increases because the reading surface of the spatial light modulator 103 is irradiated with high intensity light. .
In order to prevent the performance of the spatial light modulator from deteriorating due to the rise in temperature, a heat sink is fixed to the holder (not shown) as necessary, or the holder itself is processed into a heat sink shape. Further, a cooling fan may be provided outside the apparatus body or the like so as to face the holder unit. Radiation of the entire holder unit is performed by blowing or suction air from the cooling fan. Therefore, at this time, the holder 201 and the heat sink are formed from a metal member such as aluminum having a high thermal conductivity .

In the holder unit having the above-mentioned structure, the spatial light modulator is completely sealed except for the writing surface or the reading surface where the region is extracted by the mask. Therefore, conventionally, in order to cool the spatial light modulator, the blowing or suction air of the cooling fan is applied to the holder unit or the heat sink portion provided as necessary. That is, an indirect cooling method is employed in which the amount of heat generated in the spatial light modulator is transmitted to the holder unit side, and the amount of heat accumulated in the holder unit is radiated by the cooling fan.

[0009]

However, in an apparatus for amplifying and displaying an output target image through a spatial light modulator as shown in the prior art, a display image with high brightness can be obtained. There were such drawbacks.

Since a light flux of a strong display light source is incident on the reading side of the spatial light modulator, even a small loss of light amount at the time of reflection changes into a large amount of heat in the spatial light modulator, and the amount of heat stored is constant. When the ratio exceeds the above range, the light-shielding film inside the spatial light modulator, the alignment film of the liquid crystal, and the like are greatly deteriorated. Therefore, conventionally, the amount of heat accumulated in the spatial light modulator is radiated by cooling the holder unit accommodating the spatial light modulator from the outside with an air cooling fan. For this reason, the cooling efficiency was poor and a considerably large heat sink and a cooling fan with a large air volume had to be prepared.

Electrode wires for driving a liquid crystal are respectively soldered to ends of the transparent substrates on the two glass substrates constituting the spatial light modulator, and the spatial light modulator may be attached to a holder depending on the state. When stored, the soldered portion of the electrode wire is in contact with or very close to the holder. Therefore, when a metal holder having a high thermal conductivity is used as in the related art, when the spatial light modulator is driven, the current transmitted through the electrode wire may be conducted to the holder side, causing a leak, and as a result, the spatial light may be leaked. The voltage applied between the liquid crystals of the modulator decreases, and the final image output becomes unstable. The example concerns a voltage drop due to use of a leakage the holder of ABS or polyacetal resin (insulator) Although there is no heat is accumulated to the spatial light modulator for thermal conduction rate is extremely low, the spatial light modulator Shorten the life of the vessel itself.

Furthermore since the conventional were housed directly the spatial light modulator to the holder, the end face of the spatial light modulator part of the leakage light during the light incident on the spatial light modulator is shown in FIG. 7 212
(Hereinafter referred to as stray light) in the output image, adverse effects such as a decrease in contrast and a deterioration in uniformity.

In view of the foregoing, an object of the present invention is to solve such a conventional problem by extending the life of the spatial light modulator by using a holder structure having a high cooling efficiency and obtaining an output image by using a holder structure having a high insulating or light shielding property. It is to achieve stabilization.

[0014]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to an image output apparatus, wherein a holder for fitting and receiving a spatial light modulator and writing on a writing surface of the spatial light modulator are provided. A write mask plate for extracting a region and a read mask plate for extracting a read region on the read surface of the spatial light modulator are provided, the write mask plate is fixed to a holder, and the read mask plate is further spatially separated. An air layer is provided on the reading surface of the optical modulator and fixed to the holder.

Further, a cooling fan is provided in the main body of the apparatus in opposition to the holder unit, or the cooling fan is fixed to the holder unit, and the blowout portion or the suction portion of the cooling fan has a reading surface of the spatial light modulator and a reading mask. It was configured to face an air layer formed between the plates.

Further, the end face of the spatial light modulator is covered with a member having a high insulating property and a light shielding property, and the holder, the write mask plate and the read mask plate are formed from aluminum members. An alumite treatment or a tuffram treatment is applied to the facing surfaces.

[0017]

In the image output device configured as described above, the following operations are provided. An air flow path along the surface of the reading surface of the spatial light modulator can be secured. The cooling air from the cooling fan can be blown directly to the readout surface of the spatial light modulator. A short circuit between the electrode part of the spatial light modulator and the holder can be prevented. Generation of stray light from the end face of the spatial light modulator can be minimized.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. First, an example of a spatial light modulator used in the present embodiment will be described with reference to the drawings. There are several types of spatial light modulators that can be used in the present invention, and the structure of an optical writing type liquid crystal spatial light modulator will be described below. As shown in FIG. 5, transparent substrates 306a and 306b such as glass or plastic for holding liquid crystal molecules have transparent electrode layers 307a on their surfaces.
307b, there are provided alignment film layers 308a and 308b whose surfaces have been rubbed with a cloth such as velvet with uniform hair tips after applying a vertical alignment polyimide film. Transparent substrate 3
06a and 306b face the alignment film layers 308a and 308b side by controlling a gap via a spacer 313,
The nematic liquid crystal 311 is sandwiched.

The transparent electrode layer 307 on the writing side by light is used.
a, a photoconductive layer 309 is laminated between the alignment film layer 308a and the transparent substrate 306a on the writing side and the transparent substrate 306b on the reading side.
12a and 312b are formed. As the photoconductive layer 309, i-type, pi-type or pin-type hydrogenated amorphous silicon, ZnSe, CdSe or CdTeS
For example, a chalcogenide photoconductor such as e and an organic photoconductor such as vanadyl phthalocyanine can be used.

The photoconductive layer 309 and the alignment film layer 308a
A dielectric mirror 310 is formed between the layers.
The dielectric mirror 310 is formed by alternately laminating a λ / 4 film of a high refractive index film made of silicon or a compound of silicon and germanium and a λ / 4 film of a low refractive index oxide such as silicon dioxide or magnesium fluoride. A light-reflecting layer with a high light-shielding structure, a λ / 4 film of high-refractive-index oxide such as titanium oxide and zirconium oxide, and a λ / 4 film of low-refractive-index oxide such as silicon dioxide and magnesium fluoride And a high-reflection layer having a laminated structure in this order from the photoconductor 309 side. In the following description,
The interface between the transparent electrode 307a and the photoconductive layer 309 is the writing surface,
The surface formed by the nematic liquid crystal 311 is referred to as a reading surface.

It goes without saying that a transparent substrate having optical transmission anisotropy such as an optical fiber plate may be used as the transparent substrate 306a. In the optical writing type spatial light modulator having the above structure, the nematic liquid crystal 31
Reference numeral 1 indicates that liquid crystal molecules are initially aligned at an angle of about 0.3 to 5 degrees with respect to a perpendicular to the surfaces of the alignment film layers 308a and 308b. That is, when no electric field is applied to the nematic liquid crystal 311, the nematic liquid crystal 311 is oriented such that the liquid crystal molecules are inclined by about 0.3 to 5 degrees with respect to the perpendicular to the surfaces of the alignment film layers 308 a and 308 b. .

A bipolar pulse voltage generated by the light modulation characteristic control circuit 104 as shown in FIG. 9A is applied to the optical writing type spatial light modulator. At that time, the transparent substrate 30 of FIG.
When the writing light 108 is irradiated from the side of 6a, the impedance of the photoconductor 309 in the portion irradiated with the writing light decreases by nearly 1000 times or more, so that the effective value of the bipolar pulse voltage becomes large. The part is a nematic liquid crystal 3
11 is applied. Then, the liquid crystal molecules to which the effective value of the bipolar pulse voltage is applied have a large inclination angle with respect to the perpendicular to the surfaces of the alignment film layers 308a and 308b corresponding to the effective value. A change in refraction occurs in the nematic liquid crystal 311 in a portion irradiated with the writing light 108. Therefore, the reading element 109 irradiates the reading light 109 polarized in a specific direction from the reading side of the optical writing type spatial light modulator, and has a polarization direction perpendicular (parallel) to the polarization direction of the reading light 109. If the reflected light of the reading light 109 from the optical writing type liquid crystal spatial light modulator is detected through the
A read image in which the portion irradiated with 08 is positive (negative) is obtained.

At this time, the amplitude of the drive voltage generated by the light modulation characteristic control circuit 104 is reduced (or increased) as shown in FIG. 9B, or the frequency of the drive voltage waveform is changed as shown in FIG.
By increasing (or decreasing) the size as in (c), the brightness, contrast, and resolution of the read image can be changed, and positive / negative inversion can be performed. The driving voltage applied at this time is limited by the constituent film material and thickness of the optical writing type liquid crystal spatial light modulator, but the amplitude is 8 to 20 V and the frequency is 0.5 to 10 kHz.
In many cases.

As the driving voltage waveform applied to the optical writing type liquid crystal spatial light modulator, a periodic voltage waveform such as a sine waveform or a sawtooth waveform other than the waveform shown in FIG. 9 is applied. Needless to say, this may be done. [Embodiment 1] FIG. 1 is a sectional view showing an example of the configuration of a holder unit accommodating a spatial light modulator according to Embodiment 1 of the present invention, and FIG. 2 is a perspective view showing an assembly configuration of the holder unit. .

Reference numeral 103 denotes the spatial light modulator shown above.
And its side has a volume resistivity of 10 ⁷ Ωcm or more
A resin tape 208 having an insulating property and a low transmittance is wound.
Has been. Holder 20 for housing spatial light modulator 103
1 is aluminum alloy material with black anodized aluminum surface
It is molded from. There is a through hole in the center of the holder 201
And the spatial light modulator 103 is housed in the through portion.
Configuration. Also, the electrodes of the spatial light modulator 103
In order to route the wire, the holder 201 is
One U-shaped notch groove is provided up to the peripheral side
ing.

At this time, a writing mask 202 is fixed to the writing side surface of the holder 201 by screwing or the like. When the spatial light modulator 103 is inserted from the reading surface side of the holder 201, the writing of the spatial light modulator 103 is performed. The glass substrate surface on the insertion side comes into contact with the writing mask. The writing mask plate 202 is also made of an aluminum alloy material whose surface has been subjected to black alumite treatment with a thickness of 10 μm or more.

An opening for selectively extracting a region of the writing light output from the input optical system is provided at the center of the writing mask 202, and only the extracted light is a spatial light modulator. The light enters the write effective area 103. Therefore, in order to sharply express the edge portion in the region where the writing mask 202 has extracted the writing light, the thinner the plate thickness of the writing mask 202 is, the better. However, considering the strength and thermal expansion of the material, 0 is preferable. It is preferably about 0.2 to 0.5 mm. Alternatively, the edge of the opening of the writing mask 202 may be chamfered, and the thickness at the outermost end may be set to correspond to the above value.

Holder 20 to which write mask 202 is fixed
After the spatial light modulator 103 is inserted into the holder 1, a reading mask 204 is fixed to the holder 201 from the reading side via a strip-shaped spacer 203 by screwing or the like. At this time, the spacers 203 are positioned one by one on both ends of the reading surface of the holder base 201 with the longitudinal direction of the spacer 203 facing up and down. The readout mask plate 204 is made of an aluminum alloy material whose surface is subjected to black alumite treatment as in the case of the write mask 202.

The read mask 204 is also the write mask 2
An opening is provided at the center for selectively extracting a region of the readout light output from the output optical system as in the case of 02, and only the extracted light enters the effective readout region of the spatial light modulator 103. . Therefore, like the write mask, the read mask 2
In order to sharply represent the edge portion of the area where the writing light 04 has extracted the writing light, the thinner the plate thickness of the readout mask 204 is, the better.
mm is preferable. Alternatively, the edge of the opening of the reading mask 204 may be chamfered so that the thickness at the outermost end corresponds to the above value.

When the reading mask 204 is fixed by the intervention of the spacer 203, a gap t1 having a minute interval corresponding to the thickness of the spacer 203 is formed between the reading surface of the spatial light modulator 103 and the reading mask 204. Thus, a slit 206 penetrating in the vertical direction of the reading surface is formed in the holder unit. At this time, if the gap t1 is too large, the edge portion of the output image finally output through the readout mask 204 will be lost, and if too small, the air ventilation between the slits will be poor.
Therefore, the gap t1 is preferably about 0.2 to 0.8 mm.

Further, holder 201 of readout mask 204
A cushioning material 205 is stuck on the side by adhesive or the like,
The thickness t2 is set to be larger than the gap t1 between the reading surface of the spatial light modulator 103 and the reading mask 204. Therefore, when the reading mask 204 is fixed, the buffer material 205 is elastically deformed so that t2 = t1, so that the spatial light modulator 103 is pressed toward the writing side by the elastic force of the buffer material. At this time, the pressing force is set to a value that is sufficiently small with respect to the strength of the glass substrate 306 and the spacer 313 of the spatial light modulator 103 and does not affect the optical characteristics of the spatial light modulator. As a result, the spatial light modulator 103 is always in a state where its writing surface is pressed against the writing mask 202 with the holder unit assembled, so that the spatial light modulator 103 is placed in the holder 201 in the optical axis direction. The position is determined by the frictional force and the friction between the contact surface and the writing surface of the spatial light modulator 103 allows the space to be accommodated without play.

[0032] Here, a good polyurethane foam or Teflon volume resistivity as the material is of a and heat resistance 1 0 ⁷ Ω · cm or more cushioning material 205, a urethane rubber, heat-resistant felt material and the like are preferable. Further, an axial fan 210 for air cooling is located in the upper part of the holder unit in the apparatus main body. At this time, the axial fan 210 is installed so as to blow cooling air to the spatial light modulator 103. Then, the cooling air from the axial fan 210 flows through the outer periphery of the holder unit and the inside of the slit 206 provided in the holder unit, so that the spatial light modulator 103 is indirectly and directly cooled.

Embodiment 2 FIG. 3 is a cross-sectional view showing an example of the configuration of a holder unit accommodating a spatial light modulator according to Embodiment 2 of the present invention. FIG. 4 is a perspective view showing an assembly configuration of the holder unit. FIG.

FIG. 3 shows a configuration in which a cooling fan is added to the configuration of the holder unit in the first embodiment, and the writing mask 202 and the holder 201 are integrally formed. Therefore, description of the configuration of the holder unit is omitted here. Reference numeral 207 denotes a small cross flow fan, and the slit-shaped outlet thereof has substantially the same size as the upper slit 206 provided in the holder unit.

The cross flow fan 207 is fixed to the holder unit by a screw or the like via a buffer (not shown) so as not to transmit the vibration of the motor as a driving source to the holder unit. At this time, the outlet of the cross flow fan 207 is connected to the slit 206 of the holder unit.
Attach so that the cooling air does not leak.

With this configuration, when the cross flow fan 207 is operated, the cooling air from the fan surely passes directly through the slit, and radiates heat directly from the reading surface of the spatial light modulator 103, thereby achieving high efficiency. The spatial light modulator can be cooled. Also, the heat given to the readout mask 204 by the readout light blocked by the readout mask 204 is efficiently radiated by the cooling air being directly applied to the mask plate.

In this embodiment, the reading side of the spatial light modulator 103 is cooled, but it goes without saying that such a structure may be used on the writing side. Further, if a heat sink is fixed to the holder 201 or the holder 201 itself is processed into a heat sink shape as in the conventional example, a better heat radiation effect can be obtained.

[0038]

According to the present invention, as described above, in an image output apparatus, a holder for fitting and receiving a spatial light modulator and a readout mask plate for extracting a readout area on a readout surface of the spatial light modulator. And an air layer is provided on the reading surface of the spatial light modulator to fix the reading mask plate to the holder.

Further, a cooling fan is provided in the main body of the apparatus so as to face the holder unit, or the cooling fan is fixed to the holder unit, and the blowout portion or the suction portion of the cooling fan has a reading surface of the spatial light modulator and a reading mask. It was such as to face the air layer portion formed between the plates configuration. Further, the end face of the spatial light modulator is covered with a member having high insulating and light-shielding properties, and the holder, the write mask plate and the read mask plate are formed of an aluminum member, and at least the surface facing the spatial light modulator is formed. Since the alumite treatment or the taffram treatment is applied to this, the following effects are obtained.

Since the cooling air from the cooling fan can be directly blown on the reading surface of the spatial light modulator, the heat transfer efficiency at the time of heat radiation is improved. Therefore, deterioration of the liquid crystal, alignment film, light-shielding film, and the like in the spatial light modulator can be prevented, and the spatial light modulator itself can have a long life. In particular, when the cooling fan is integrated with the holder, the cooling air from the cooling fan can be more efficiently blown to the reading surface of the spatial light modulator, and the size of the device can be reduced.

A member constituting the holder unit is formed from an aluminum member, and alumite treatment or tuffram treatment is performed on the surface to ensure insulation between the spatial light modulator and the holder unit. The voltage is stable, and a high-quality output image is always obtained. This also reduces maintenance such as replacement of parts due to a short circuit accident as in the prior art. Further, by performing such a surface treatment, a metal member having high thermal conductivity can be used for the holder, so that a holder having good heat radiation characteristics can be obtained.

Since the spatial light modulator is covered with a member having a high insulating property and a light-shielding property, it is possible to reduce stray light from entering the end face of the spatial light modulator and to secure the insulating property. Therefore, high image quality such as improvement in contrast and uniformity of an output image can be achieved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a holder unit according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an assembly configuration of the holder unit according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating another example of the configuration of the holder unit according to the second embodiment of the present invention.

FIG. 4 is a perspective view showing an assembly configuration of a holder unit according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram showing an example of a spatial light modulator used in an embodiment of the present invention.

FIG. 6 is an explanatory diagram showing an example of an image output device using a conventional spatial light modulator.

FIG. 7 is an explanatory view showing an example of a holder unit for accommodating a conventional spatial light modulator.

FIG. 8 is a perspective view showing an assembling structure of a holder unit for accommodating a conventional spatial light modulator.

FIG. 9 is an explanatory diagram showing driving waveforms for the spatial light modulator used in the embodiment of the present invention.

[Explanation of symbols]

 103 Spatial light modulator 201 Holder 202 Write mask 203 Spacer 204 Read mask

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02F 1/135

Claims (6)

(57) [Claims] A spatial light modulator; an input optical system for writing an input target image on a writing surface of the spatial light modulator;
Output optics for imaging an image on the readout surface of the spatial light modulator
System, a holder accommodating the spatial light modulator, and the space
A writing mask for extracting a writing area on a writing surface of an optical modulator.
Disk and a reading area on a reading surface of the spatial light modulator.
A readout mask to be extracted.
The readout mask plate is positioned on the readout surface of the spatial light modulator.
Air layer and fixed to the holder.
The spatial light of the writing mask and the reading mask;
Anodized or tuffram facing modulator
An image output device characterized by being processed . 2. The writing mask and the reading mask.
2. The metal member is formed of an aluminum member.
The image output device as described in the above. 3. The apparatus according to claim 3, wherein said holder is formed of an aluminum member.
The surface of the holder facing the spatial light modulator is anodized.
Claims that have been processed or tuffram processed
Item 3. The image output device according to item 1 or 2 . 4. A spatial light modulator, comprising:
An input optical system for writing on a writing surface of the inter-light modulator;
Output optics for imaging an image on the readout surface of the spatial light modulator
System, a holder accommodating the spatial light modulator, and the space
A writing mask for extracting a writing area on a writing surface of an optical modulator.
Disk and a reading area on a reading surface of the spatial light modulator.
A readout mask to be extracted.
The reading mask with respect to the reading surface of the spatial light modulator.
An air layer is provided and fixed to the holder,
The spatial light modulation is performed by elastically deforming the buffer member thicker than the gas layer.
Between the readout surface of the detector and the readout mask.
The spatial light modulator is pressed against the writing mask
An image output device, comprising: 5. The buffer member has a volume resistivity of 10 ^7.
5. The method according to claim 4, wherein the resistance is Ω · cm or more.
Image output device. Wherein said holder and said write mask image output apparatus according to claim 4 or 5, characterized in that molded integrally.