JP2004317653A - Light modulation element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a light modulation element in which an absorption at a mirror or at a light shielding film is extremely low, and which is endurable against high power laser light, and to improve an operational reliability. <P>SOLUTION: In a reflection type light modulation element 100 of a microelectromechanical type in which the reflection optical path of light is varied by dislocating a miniature reflection body 101, an interference mirror 111 having non-absorbing characteristic of light over the spectrum range of incident light is provided at least in the light incident region of the reflection body 101. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a light modulation element suitable for use in an on-demand digital exposure apparatus used in a photolithography process, an image forming apparatus using digital exposure, a projection display apparatus such as a projector, or a micro display apparatus such as a head-mounted display. About.
[0002]
[Prior art]
As this type of light modulation element, for example, a liquid crystal element, a micro electro mechanical (MEMS) light modulation element, and the like are known. In particular, a microelectromechanical light modulation element is excellent in resolution and responsiveness, and is suitable for application to the above fields. For example, a deflection mirror type DMD element is known as a reflection type light modulation element, and is used in a projector display device or a digital exposure device. Further, as the transmissive light modulation element, a mechanical shutter type such as a slide type or a flap type is known.
[0003]
Prior art document information related to the invention of this application includes the following.
[Patent Document 1]
JP 2000-131628 A
[Patent Document 2]
JP 2000-131630 A
[0004]
As shown in FIG. 6, the image recording apparatus using the light modulation element disclosed in Patent Document 1 modulates the light emitted from the light source 1 by the light modulation element, and the recording medium on the recording rotary drum 3 is used. 5 is a reflection diffraction grating in which a high-power laser is used as the light source 1 and a plurality of grating light valve elements are arranged at least in the width direction of the recording rotary drum 3. It is configured as a light modulation array element 7 of a type.
In FIG. 6, reference numerals 9 to 15 denote optical systems of the optical head, 9 is a first lens (cylindrical lens), 11 is a second lens, 13 is a third lens, and 15 is a fourth lens. Reference numeral 17 denotes a slit plate that removes light reflected by the light modulation array element 7 (zero-order reflected light) from the incident optical path of the third lens 13.
[0005]
According to this image recording apparatus, since the light modulation array element 7 of the reflection diffraction grating type is included in the light modulation section, it can withstand high-power laser light and perform high-speed image recording even on a heat mode recording medium. Thus, a highly reliable image recording apparatus capable of achieving the above can be obtained.
[0006]
Further, as shown in FIG. 7, the optical pickup device including the mirror device disclosed in Patent Document 2 includes a first substrate 23 on which the first electrode 21 is formed, and at least the first substrate 23. A first electrode having a first electrode 21 and a mirror portion 29 having a second electrode 25 formed on an opposite surface sandwiching the air gap and a mirror film 27 formed on the opposite surface; In the mirror device in which the mirror portion 29 is displaced by an electrostatic force generated while applying a voltage difference between the first electrode 25 and the second electrode 25, the mirror film 27 includes a mirror including any one of silver, gold, and aluminum. Metal film and dielectric film formed on mirror metal film, for example, 100 nm thick SiO₂Film and this SiO₂For example, Si having a thickness of 75 nm is formed on the film.₃  N₄  It is characterized by having a film.
[0007]
According to this optical pickup device, the displacing mirror 29 has sufficient rigidity and can have a reflectivity of 95% or more, preferably 98% or more. The characteristics can be enhanced.
[0008]
[Problems to be solved by the invention]
By the way, in the use of the light modulation element in the above-described field, there is a demand for further higher resolution and higher speed, and with the increase of incident light power, the light modulation element is required to have high power tolerance. For example, in a conventional image recording apparatus using a light modulation element, a semiconductor laser having a normal power is used as a light source. For recording media with high sensitivity (photo mode), such as photographic film or lith film for printing (silver salt is used as the photosensitive material), this normal power semiconductor laser can be used for practical recording of images. Although it can be performed, for a transfer type recording medium (heat mode), the sensitivity is reduced by 3 to 5 digits, so that a normal power semiconductor laser is irradiated for a long time (exposure). ) Is required, and the processing time is several thousand to several hundred thousand times, which is not practical. For this reason, when the recording medium is in the heat mode, it is desirable to use a high-power semiconductor laser as the light source.
Recently, on-demand digital exposure without using conventional masks is expected in photolithography processes such as high-density printed circuit board wiring, circuit patterning, flat panel display wiring and circuit patterning, and semiconductor circuit patterning. ing. In this case, it is necessary to perform high-resolution exposure with an exposure tact time equal to or longer than that of conventional mask exposure. Therefore, the power density of light incident on the light modulation element increases, and the light modulation element is required to have high light power resistance. Furthermore, the wavelength of incident light ranges from UV light (from deep UV light such as excimer laser to near UV light such as mercury lamp) to visible light (up to 550 nm) and operates with almost no absorption for each wavelength used. A highly reliable light modulation element is required.
However, in the conventional light modulation element, for example, in the case of the deflection mirror system, a metal such as Al or Ni or a reflective semiconductor is used as the mirror, and in the case of the mechanical shutter system, a metal such as Al or Ni is used as the movable light shielding film. In addition, Si and C semiconductors are used. These mirror materials or light-shielding materials have light absorption of at least several percent in the case of UV light, visible light, and near-infrared light, which are objects in the above field. In the image recording apparatus using the light modulation element disclosed in Patent Document 1, the reflection diffraction grating type light modulation element causes interference by displacing the displacement portion by λ / 4 with respect to the wavelength λ of incident light. Although the incident light is modulated, it is necessary to precisely displace the displacement portion to λ / 4 for each of the plurality of displacement portions of each element or for each element. However, it is difficult to precisely displace a plurality of displacement portions and the like by λ / 4. For this reason, the contrast dropped when the variation of the elements and the variation over time were taken into account. Further, when the displacement of λ / 4 cannot be precisely controlled, there is a problem that the light utilization efficiency when high power light is incident is lowered. Further, in the optical pickup device including the mirror device disclosed in Patent Document 2, a reflection enhancement film (SiO 2) is formed on the mirror metal film.₂, Si₃N₄) Is provided to reduce light absorption, but it is disclosed that 1 to 2% of absorption exists. In high power laser systems, even a few percent absorption can cause significant effects. In such a case, the element temperature is excessively increased, and in the worst state, the light modulation element may be broken down and the operation reliability may be lowered.
The present invention has been made in view of the above situation, and provides a light modulation element that can withstand a high-power laser beam (that is, has high power resistance) with very little absorption in a mirror or a light shielding film. The purpose is to increase the light use efficiency and improve the operation reliability.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a light modulation element according to claim 1 of the present invention is a microelectromechanical reflection deflection light modulation element that changes a light reflection optical path by displacing a minute reflector. An interference mirror having a non-absorbing property over a spectrum region of incident light is provided at least in the light incident region of the reflector.
[0010]
In this light modulation element, the light absorption of the reflector exposed to the laser beam irradiation is extremely less than that in the case where a metal filter exhibiting absorption is used as the reflection film, and heat generation due to the light absorption of the reflector is reduced. Thereby, the high power tolerance with respect to the high output laser in the light modulation element is further increased, and the operation reliability can be improved.
In addition, the reflection deflection type light modulation element does not require a displacement portion that requires precise displacement like the reflection diffraction grating type, and can simplify the mechanism and reduce variations generated from element to element.
Furthermore, since the light is directly reflected, the contrast is high. However, by attaching a dielectric mirror, light absorption at the reflecting surface is eliminated, and the reflectance can be improved and the light utilization efficiency can be increased.
[0011]
The light modulation element according to claim 2 is the light modulation element according to claim 1, wherein a microlens having a condensing region is provided at least on a light incident side, and the reflector is provided in the condensing region. It is arranged.
[0012]
In this light modulation element, the light utilization efficiency is increased in the reflection deflection type light modulation element, and bright modulated light can be obtained with high efficiency even in a small opening area. In addition, the light utilization efficiency is increased, and the reflector can be made smaller than when no microlens is provided. This also reduces heat generation due to light absorption of the reflector, and further reduces the drive energy of the reflector. As a result, the modulation operation can be speeded up.
[0013]
The light modulation element according to claim 3 is a micro electromechanical transmission type light modulation element that controls the transmittance of incident light by displacing a minute light shield, and at least the light incident on the light shield. The region is provided with an interference mirror having non-absorbing properties over the spectral range of incident light.
[0014]
In this light modulation element, light absorption of the light shielding body exposed to the laser beam irradiation is extremely less than when a metal filter that exhibits absorption is used as the reflection film, and heat generation due to light absorption of the light shielding body is reduced. Thereby, the high power tolerance with respect to the high output laser in the transmission type light modulation element is further increased, and the operation reliability can be improved.
[0015]
A light modulation element according to a fourth aspect is the light modulation element according to the third aspect, wherein a microlens having a condensing region is provided at least on a light incident side, and the light-shielding body is provided in the condensing region. It is arranged.
[0016]
In this light modulation element, the light use efficiency is increased in the transmission type light modulation element, and bright modulated light can be obtained with high efficiency even in a small opening area. In addition, the light use efficiency is increased, and the light shielding body can be made smaller compared to the case where no microlens is provided. This also reduces heat generation due to light absorption of the light shielding body, and further reduces the driving energy of the light shielding body. As a result, the modulation operation can be speeded up.
[0017]
The light modulation element according to claim 5 is the light modulation element according to claim 1 or 3, wherein the light modulation element has a light non-absorbing property in a light incident region other than the light modulation region over a spectral range of incident light. An interference mirror is provided.
[0018]
In this light modulation element, in both the reflection type and the transmission type light modulation elements, light absorption in portions other than the light modulation region irradiated with the laser beam is extremely reduced, and heat generation due to light absorption of the entire element is reduced. The As a result, the high power tolerance of the light modulation element with respect to the high-power laser is further increased, so that the light utilization efficiency is improved and the operation reliability can be improved.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a light modulation element according to the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram showing a light modulation section of a reflection type light modulation element according to the present invention, and FIG. 2 is an operation explanatory view of the light modulation element shown in FIG. In the following description, the reflection type light modulation element refers to a reflection deflection type light modulation element (mainly a DMD element), and the reflection deflection type light modulation element is a grating light valve element. Unlike the reflection diffraction grating type light modulation element represented by (2), it is a modulation element that deflects by directly changing the optical path of incident light by a reflector. Specifically, it refers to a deflection mirror type light modulation element or the like.
[0020]
The light modulation element 100 according to the present embodiment constitutes a microelectromechanical reflection type light modulation element that changes the reflection optical path of light by displacing the minute reflector 101. That is, a pixel circuit 105 made of CMOS is formed on the transparent substrate 103 for each pixel region. A pair of fixed electrodes 107 a and 107 b are formed on the pixel circuit 105 of the transparent substrate 103.
[0021]
A reflector 101 that is a movable part is provided above the transparent substrate 103. The reflector 101 includes a movable plate 109 fixed to the hinge 107, an interference mirror 111 formed on the surface of the movable plate 109, and a movable electrode 113 that protrudes and is fixed to the hinge 107 in a wing shape. The hinge 107 is made of a flexible material, and both end portions in the direction perpendicular to the paper surface of FIG. Therefore, the movable plate 109 and the interference mirror 111 integrated with the hinge 107 are supported so as to be swingable around the rotation axis in the direction perpendicular to the paper surface of FIG.
[0022]
The light modulation element 100 is reflected as shown in FIG. 2 by a Coulomb force due to static electricity when a voltage is applied between the movable electrode 113 and the fixed electrode 107a or the fixed electrode 107b by an electric signal from the pixel circuit 105. The body 101 is oscillated and displaced (electromechanical operation) and operates so as to change the reflected light path of light incident on the reflector 101. That is, a deflection mirror mechanism is configured.
[0023]
The light modulation element 100 can be a light modulation element array in which a plurality of elements are arranged one-dimensionally or two-dimensionally. Thus, according to the two-dimensional matrix-shaped light modulation element array in which a plurality of rows of the light modulation elements 100 are arranged, an image comparable to the cathode ray tube in resolution can be displayed by the mirror density. .
[0024]
The light modulation element 100 is provided with a microlens 115 having a condensing region at least on the light incident side, and the reflector 101 is disposed in the condensing region. In the case of FIGS. 1 and 2, one microlens 115 is shown for simplicity, but the microlens 115 is arranged corresponding to a single or a plurality of reflected light paths that differ depending on the swing of the reflector 101. Established. Further, the microlens 115 may be arranged not only for the reflected light path but also for the incident light path. When the light modulation element 100 is a one-dimensional or two-dimensional light modulation element array, the microlens 115 is a microlens array in which a plurality of elements are arranged in correspondence with the reflector 101. Can do.
[0025]
By the way, the reflection mirror 101 of the light modulation element 100 is provided with the interference mirror 111 described above. The interference mirror 111 is non-absorbing over the spectral range of incident light at least in the light incident region of the reflector 101. The interference mirror 111 is a dielectric thin film that reflects interference in a specific wavelength region by using interference caused by a thin film of about the light wavelength. The dielectric thin film may be a dielectric multilayer film in which dielectrics having different thicknesses and refractive indexes are formed in multiple layers.
[0026]
As the dielectric multilayer film, the following materials can be used for visible light, infrared rays, or ultraviolet rays.
[For visible light and infrared rays]
a. As a high refractive index material (a material having a refractive index of about 1.8 or more),
TiO₂, CeO₂, Ta₂O₅, ZrO₂, Sb₂O₃, HfO₂, La₂O₃, NdO₃, Y₂O₃, ZnO, Nb₂O₅
b. As a relatively high refractive index material (a material having a refractive index of approximately 1.6 to 1.8 or more),
MgO, Al₂O₃, CeF₃, LaF₃, NdF₃
c. As a low refractive index material (a material having a refractive index of about 1.5 or less),
SiO₂, AlF₃, MgF₂, Na₃AlF₆, NaF, CaF₂, BaF₂
[For UV light]
a. As a high refractive index material (a material having a refractive index of about 1.8 or more),
ZrO₂, HfO₂, La₂O₃, NdO₃, Y2O₃,
Or
TiO₂, Ta₂O₅, ZrO₂
(However, the wavelength of light is approximately 360 nm to 400 nm)
b. As a relatively high refractive index material (a material having a refractive index of approximately 1.6 to 1.8 or more),
MgO, Al₂O₃, LaF₃, NdF₃
c. As a low refractive index material (a material having a refractive index of about 1.5 or less),
SiO₂, AlF₃, MgF₂, Na₃AlF₆, NaF, LiF, CaF₂
[0027]
The interference mirror 111 made of such a dielectric multilayer film has very little light absorption over the spectral range of incident light. For example, light absorption is on the order of a few millionths. In the present specification, having such very little light absorption is referred to as “having no light absorption”. The interference mirror 111 having non-light absorption is distinguished from a metal mirror that exhibits light absorption. Here, light non-absorptivity is applicable only to a limited spectral range. This is because every substance always shows absorption at some wavelength.
[0028]
Further, in the light modulation element 100, the same interference mirror 111 as described above having a light non-absorption property over the spectrum region of incident light is provided in a light incident region other than the light modulation region. In the case of the light modulation element 100, the light incident region other than the light modulation region is provided between the microlens 115 and the reflector 101, has a light incident / reflecting opening with respect to the reflector 101, and has an adjacent reflection. Examples include a mask unit that covers the gap between the bodies 101 and prevents stray light from entering, and a mask unit that is formed between adjacent microlenses 115 to prevent stray light from entering.
[0029]
By providing the interference mirror 111 in such a light incident region other than the light modulation region, light absorption in a portion other than the light modulation region irradiated with the laser beam is extremely reduced, and heat generation due to light absorption of the entire element is reduced. Is done. Thereby, the high power tolerance with respect to the high output laser of the light modulation element 100 is further increased, and the operation reliability is improved.
[0030]
As described above, according to the light modulation element 100 described above, the light absorption of the reflector 101 that is exposed to the laser beam irradiation is extremely small as compared with the case where a metal filter that exhibits absorption is used as the reflection film. Heat generation due to light absorption is reduced. Thereby, the high power tolerance with respect to the high output laser in the reflection type light modulation element 100 is further increased, and the operation reliability can be improved.
[0031]
Further, by providing the microlens 115, the light use efficiency is increased, and high-efficiency and bright modulated light can be obtained even in a small opening area. Further, the light utilization efficiency is increased, and the reflector 101 can be formed smaller than the case where the microlens 115 is not provided. This also reduces heat generation due to light absorption of the reflector 101, and further, the reflector 101. As a result, the driving speed of the modulation operation can be increased.
Although the reflection type light modulation element has been described as an example in the above, the present invention can also be applied to a transmission type light modulation element in which a reflector is displaced as an element constituting the modulation element. That is, a transmissive light modulation element in which an interference mirror is provided at a portion where light is reflected in the light modulation element can be applied.
[0032]
Next, a second embodiment of the light modulation element according to the present invention will be described.
FIG. 3 is a block diagram showing a light modulation unit of a transmission type light modulation element according to the present invention, FIG. 4 is a plan view of the light modulation element shown in FIG. 3, and FIG. 5 is an operation of the light modulation element shown in FIG. It is explanatory drawing. In addition, the same code | symbol is attached | subjected to the member same as the member shown in FIG. 1, and the overlapping description shall be abbreviate | omitted.
[0033]
The light modulation element 200 according to this embodiment is a transmission type light modulation element that controls the transmittance of incident light by displacing a minute light shield 201. That is, on the transparent substrate 203, a pair of fixed electrodes 205a and 205b are arranged with the light shielding body 201 sandwiched in the left-right direction in FIG. As shown in FIG. 4, the light shielding body 201 is fixed to a support portion 209 on the transparent substrate 203 via a flexible beam 207. Thereby, the light-shielding body 201 is configured to be movable in the left-right direction.
[0034]
The light shield 201 is formed with movable electrodes 212a and 212b shown in FIG. The fixed electrodes 205a and 205b are provided with teeth 205c protruding from the opposing surface. Further, the light shielding body 201 has teeth 201a protruding from the left and right ends. The teeth 205c and the teeth 201a of the fixed electrodes 205a and 205b and the movable electrodes 212a and 212b are alternately meshed with each other.
[0035]
A transmissive opening 211 is formed between the fixed electrodes 205a and 205b. The light shielding body 201 is moved to a position that overlaps the transmission opening 211 and a position that does not overlap. That is, the light shielding body 201 and the transmission opening 211 constitute a mechanical shutter mechanism.
[0036]
The light modulation element 200 is applied with a voltage between the movable electrode 212a and the fixed electrode 205a or between the movable electrode 212b and the fixed electrode 205b by an electric signal from the pixel circuit 105, so that the light shielding element 201 is generated by the Coulomb force due to static electricity. Is displaced left and right (electromechanical operation), and operates so as to change the transmittance of light that is transmitted through the transmission aperture 211.
[0037]
Similar to the light modulation element 100, the light modulation element 200 can be a light modulation element array in which a plurality of elements are arranged one-dimensionally or two-dimensionally. Further, the light modulation element 200 is provided with a microlens 115 having a condensing region at least on the light incident side, and a light shielding body 201 is disposed in the condensing region. When the light modulation element 200 is a one-dimensional or two-dimensional light modulation element array, the microlens 115 is a microlens array in which a plurality of microlenses 115 are arranged corresponding to the transmission openings 211. Can do.
[0038]
Also in this light modulation element 200, the light shielding body 201 is provided with an interference mirror 111 similar to the above. The interference mirror 111 has a light non-absorbing property over the spectral range of incident light at least in the light incident region of the light blocking body 201.
[0039]
In the light modulation element 200, a light shielding film 213 is provided in a light incident region other than the light modulation region. The light shielding film 213 has an opening 215 corresponding to the transmission opening 211. Also on the surface of the light shielding film 213, the same interference mirror 111 as described above having non-absorbing properties over the spectral range of incident light is provided. As a result, as in the case of the light modulation element 100 described above, the high power resistance of the light modulation element 200 to the high-power laser is further increased, and the operation reliability is improved.
[0040]
As a light modulation operation of the light modulation element 200, as shown in FIG. 4A, when a voltage is applied to the fixed electrode 205a and the movable electrode 212a, the light shielding body 201 is moved to the left side, and the transmission aperture 211 is blocked and becomes opaque due to the light blocking effect. On the other hand, as shown in FIGS. 4B and 5, when a voltage is applied to the fixed electrode 205 b and the movable electrode 212 b, the light shielding body 201 is moved to the right side, and the light shielding body 201 opens the transmission opening 211. , The light transmittance is increased.
[0041]
According to this light modulation element 200, the light absorption of the light shielding body exposed to the laser beam irradiation is extremely less than the case where a metal filter exhibiting absorption is used as the reflection film, and the heat generation due to the light absorption of the light shielding body is reduced. Is done. Thereby, the high power tolerance with respect to the high output laser in the transmission type light modulation element is further increased, and the operation reliability can be improved.
[0042]
Since the microlens 115 is provided, the light use efficiency is increased in the transmissive light modulation element 200, and high-efficiency and bright modulated light can be obtained even in a small opening area. In addition, the light use efficiency is increased, and the light shielding body 201 can be formed small compared to the case where the microlens 115 is not provided. This also reduces heat generation due to light absorption of the light shielding body 201. As a result, the driving speed of the modulation operation can be increased.
[0043]
Further, according to the light modulation element 200, the fixed electrodes 205a and 205b and the movable electrodes 212a and 212b are formed in a comb shape, whereby the displacement amount of the light shield 201 can be increased, and the position control by voltage is performed. Can be made easier.
[0044]
In the above embodiment, the case where the present invention is applied to the deflecting mirror mechanism and the mechanical shutter mechanism has been described as an example. However, the present invention can also be provided at the upper end of the support column in the form of a cantilevered light shield. The same effect can be obtained even when employed in a so-called flap type mechanical shutter mechanism that controls the transmitted light by flexing the lens.
[0045]
【The invention's effect】
As described above in detail, according to the light modulation element of the first aspect of the present invention, the reflector is displaced (electromechanical operation) by the Coulomb force caused by static electricity, and the light incident on the reflector is reflected. In the reflection deflection type light modulation element that changes the optical path, an interference mirror that has non-absorption of light over the spectral range of incident light is provided at least in the light incident region of the reflector. Compared with the case of using as a reflective film, the light absorption of the reflector exposed to the laser beam irradiation is extremely reduced, and heat generation due to the light absorption of the reflector is reduced. As a result, it is possible to further improve the high power resistance against the high output laser in the reflection type light modulation element, and to improve the operation reliability.
Further, the reflection deflection type light modulation element can reduce the variation from element to element by simplifying the mechanism as compared with the reflection diffraction grating type. Further, the reflection deflection type light modulation element has high contrast because it directly reflects light, but by attaching a dielectric mirror, there is no light absorption at the reflection surface, and the reflectance is improved and the light utilization efficiency is increased.
[0046]
According to the light modulation element of the second aspect, in the reflection deflection type light modulation element, the microlens having the light collection region is provided at least on the light incident side, and the reflector is disposed in the light collection region. As a result, the light utilization efficiency is increased, and even in a small opening area, bright modulated light can be obtained with high efficiency. In addition, since the light utilization efficiency is increased and the microlens is not provided, the reflector can be made smaller. This also reduces heat generation due to light absorption of the reflector, and further driving the reflector. It is possible to reduce the energy and to increase the speed of the modulation operation.
[0047]
According to the light modulation element of the third aspect, in the transmission type light modulation element for controlling the transmittance of incident light by displacing the light shielding body (electromechanical operation) by the Coulomb force caused by static electricity, Interference mirrors that are non-absorbing over the spectral range of incident light are provided in the light incident area, so that the light shielding is exposed to laser beam irradiation compared to the case where a metal filter that exhibits absorption is used as a reflective film. The light absorption of the body is extremely reduced, and heat generation due to the light absorption of the light shielding body is reduced. As a result, it is possible to further improve the high power resistance against the high output laser in the transmission type light modulation element, and to improve the operation reliability.
[0048]
According to the light modulation element of claim 4, in the transmission type light modulation element, the microlens having the light collection region is provided at least on the light incident side, and the light blocking body is disposed in the light collection region. Light utilization efficiency is increased, and high-efficiency and bright modulated light can be obtained even in a small opening area. In addition, since the light utilization efficiency is increased and the micro-lens is not provided, the light-shielding body can be made smaller. This also reduces heat generation due to light absorption of the light-shielding body, and further driving the light-shielding body. It is possible to reduce the energy and to increase the speed of the modulation operation.
[0049]
According to the light modulation element of the fifth aspect, since the interference mirror having the light non-absorption property is provided in the light incident region other than the light modulation region over the spectrum region of the incident light, the reflection type and the transmission type are provided. In any of the light modulation elements, light absorption in a portion other than the light modulation region irradiated with the laser beam is extremely reduced, heat generation due to light absorption of the entire element is reduced, and high power resistance of the light modulation element to a high output laser. Can be further enhanced.
[Brief description of the drawings]
FIG. 1 is a configuration diagram illustrating a light modulation unit of a reflective light modulation element according to the present invention.
FIG. 2 is an operation explanatory diagram of the light modulation element shown in FIG. 1;
FIG. 3 is a configuration diagram illustrating a light modulation unit of a transmission type light modulation element according to the present invention.
4 is a plan view of the light modulation element shown in FIG. 3. FIG.
FIG. 5 is an operation explanatory diagram of the light modulation element shown in FIG. 3;
FIG. 6 is a configuration diagram of an image recording apparatus having a conventional reflection diffraction grating type light modulation array element in a light modulation section.
FIG. 7 is a configuration diagram of an optical pickup device including a conventional mirror device.
[Explanation of symbols]
100, 200 ... Light modulation element
101 ... Reflector
111 ... Interference mirror
115 ... Microlens
201: Shading body

Claims (5)

A micro-electromechanical reflection-deflection type light modulation element that changes a reflection optical path of light by displacing a minute reflector,
An optical modulation element, wherein an interference mirror having non-absorbing properties is provided at least in a light incident region of the reflector over a spectrum region of incident light. The light modulation element according to claim 1,
A light modulation element, wherein a microlens having a condensing region is provided at least on a light incident side, and the reflector is disposed in the condensing region. A micro electromechanical transmission type light modulation element that controls the transmittance of incident light by displacing a minute light shielding body,
An optical modulation element characterized in that an interference mirror having non-absorbing properties is provided at least in a light incident region of the light shielding body over a spectrum region of incident light. The light modulation element according to claim 3,
A light modulation element characterized in that a microlens having a condensing region is provided at least on the light incident side, and the light blocking body is disposed in the condensing region. The light modulation element according to claim 1 or 3, wherein
An optical modulation element, wherein an interference mirror having a non-absorbing property over a spectrum region of incident light is provided in a light incident region other than the light modulation region.

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