JP4804358B2 - Spatial light modulation device, optical processing device, and method of using coupling prism - Google Patents

Description

  The present invention relates to a spatial light modulation device, an optical processing device, a coupling prism, and a method of using the coupling prism.

  In a display, incident light is obliquely incident on a reflective spatial light modulator (hereinafter referred to as a reflective SLM) with a hologram color filter by a coupling prism (see, for example, Patent Document 1), or a reflection hologram on the back side. Is read obliquely by a prism with respect to a transmissive spatial light modulation element SLM (hereinafter referred to as a transmissive SLM) in which is disposed (see, for example, Patent Document 2), or a color wheel made up of a plurality of color filters is reflected by a reflecting mirror. It has been proposed to perform oblique reading (see, for example, Patent Document 3). Here, the reflection type SLM is a spatial light modulation element (hereinafter referred to as SLM) that has an element reflection surface and reflects incident light. On the other hand, the transmissive SLM is an SLM used by transmitting incident light.

  However, since all of the apparatuses described in Patent Documents 1 to 3 are displays, not only simple illumination light that does not contain information such as parallel light or spherical waves, but also light that includes aberration or information (diffraction). Arbitrary processing such as phase modulation and amplitude modulation cannot be performed on arbitrary light such as light including components.

  On the other hand, as an optical processing apparatus that can perform arbitrary phase modulation or amplitude modulation on arbitrary light using an SLM, for example, a wavefront compensation system, a pattern forming system, a holography system, a 3D display system, an optical information processing Systems etc. are known.

  For example, in the pattern forming optical system 600 shown in FIG. 1, the output light from the laser 602 is converted into parallel light having a desired beam diameter via a spatial filter 604 including a lens 603 and a pinhole 605 and a collimator lens 606. The light is converted and incident obliquely on the reflective SLM 608 as readout light. The reflective SLM 608 displays a predetermined hologram image. The readout light is phase-modulated by the reflective SLM 608, reflected obliquely by the element reflection surface, and emitted from the reflective SLM 608. The readout light is Fourier transformed by the Fourier transform lens 610 to form a desired pattern on the output surface 612 (see, for example, Patent Document 4). Here, the reflective SLM has a higher effective aperture ratio and less light loss than the transmissive SLM.

In the 4f optical system 620 shown in FIG. 2, a prism 624, a Fourier transform lens 626, and a reflective SLM 628 are disposed between the input surface 622 and the output surface 630. The readout light exiting the input surface 622 is reflected by the slope of the prism 624 and guided to the Fourier transform lens 626. The readout light passes through the Fourier transform lens 626 and then enters the reflective SLM 628 obliquely. The readout light is modulated by the reflective SLM 628 and reflected by the element reflection surface. Thereafter, the readout light passes through the Fourier transform lens 626 again, is reflected by the slope on the opposite side of the prism 624, and forms an image on the output surface 630. As described above, one Fourier transform lens 626 has two functions of Fourier transform on the incident side and Fourier transform on the output side (see, for example, Patent Document 4).
Japanese Patent Laid-Open No. 11-194330 (page 4-5, FIG. 1) JP 2002-517781 A (pages 16-18, FIG. 5) JP 2001-4930 A (page 4-6, FIG. 1) Japanese Unexamined Patent Publication No. 2000-171824 (page 3-4, FIGS. 3 and 7)

  However, in the pattern forming optical system 600 described with reference to FIG. 1, the optical axis is bent obliquely by the reflective SLM 608. This makes it difficult to design, assemble and adjust the optical system. Further, if the pattern forming optical system 600 is to be constructed on a rectangular substrate, the area of the substrate becomes large and it is difficult to reduce the size.

  In the 4f optical system 620 described with reference to FIG. 2, both incident light and outgoing light pass through the peripheral portion of the Fourier transform lens 626, and the adverse effect of off-axis aberrations is increased. Further, since the diameter of the Fourier transform lens 626 becomes large, it is difficult to design and manufacture the lens. Conversely, if the diameter of the Fourier transform lens 626 is reduced, the effective beam diameter must be reduced. Further, in order to sufficiently separate the incident light and the emitted light, the focal length of the Fourier transform lens 626 must be increased. In addition, the focal lengths of the Fourier transform lenses on the entrance side and the exit side cannot be made different.

  Therefore, it is conceivable to configure the 4f optical system as shown in FIG. The 4f optical system 640 includes an input surface 622, a Fourier transform lens 626-1, a reflective SLM 628, a Fourier transform lens 626-2, and an output surface 630. Both the distance between the input surface 622 and the Fourier transform lens 626-1 and the distance between the Fourier transform lens 626-1 and the reflective SLM 628 are equal to the focal length of the Fourier transform lens 626-1. Yes. The distance between the reflective SLM 628 and the Fourier transform lens 626-2 and the distance between the Fourier transform lens 626-2 and the output surface 630 are both equal to the focal length of the Fourier transform lens 626-2. It has become. A parallel light projection optical system is disposed on the front side of the input surface 622 to project parallel light onto the input surface. According to the 4f optical system 640, the above-described problem in the 4f optical system 620 described with reference to FIG. 2 can be solved.

  However, the optical axis 650 on the input side and the optical axis 652 on the output side intersect obliquely at an angle that is not perpendicular. Accordingly, it is not easy to accurately set the straight line formed by the optical axis 650 and the straight line formed by the optical axis 652 and to accurately arrange the input side and output side optical devices on these straight lines.

  Further, when creating an assembly substrate for assembling the 4f optical system 640, an oblique straight line formed by the optical axes 650 and 652 must be created on the substrate by machining. However, since the optical axes are not perpendicular to each other, a special jig is required.

  Moreover, when the optical device is attached to the assembly substrate, the optical adjustment based on the parallel line and the vertical line with respect to the optical axis cannot be performed, so that the attachment is difficult.

  Further, the distance (optical path length) between the input surface 622 and the Fourier transform lens 626-1, the distance (optical path length) between the Fourier transform lens 626-1 and the reflective SLM 628, the reflective SLM 628 and the Fourier transform lens 626. −2 (optical path length) and the distance (optical path length) between the Fourier transform lens 626-2 and the output surface 630 need to be matched with accuracy within the depth of focus. When any device moves in the optical axis direction due to transportation or vibration, it is necessary to adjust the position of the device in the optical axis direction. However, since the reflection type SLM 628 is an inflection point of the optical axis, when the position of the reflection type SLM 628 is changed from the position I to the position II, for example, as shown in FIG. The axis 650 and the optical axis 652 do not coincide with each other on the reflective SLM 628, and either the optical axis 650 or the optical axis 652 must be moved in a direction perpendicular to the optical axis.

  However, it is practically impossible to move the optical axis in a direction perpendicular to the optical axis because it affects the positions of all devices arranged on the optical axis.

  As described above, even in the position adjustment in the optical axis direction, a positional shift in a plane perpendicular to the optical axis occurs, so that the position adjustment in the optical axis direction of the 4f optical system 640 is not easy.

  The reflective SLM 628 is moved along the bisector of the two optical axes 650 and 652. Since the bisector is not perpendicular to the two optical axes 650 and 652, it is difficult to move with high accuracy. Moreover, since it is necessary to keep the positional accuracy of the reflective SLM 628 high in a plane perpendicular to the bisector, position adjustment in the optical axis direction is very difficult.

  It is also conceivable to provide two reflective SLMs 628 (hereinafter referred to as reflective SLMs 628-1 and 628-2) as in the 4f optical system 660 shown in FIG. Since two reflection-type SLMs 628 are used, there are two bent portions of the optical axis, and three optical axes 654, 650, and 652 extending in different directions are generated. Lenses 626-1 and 626-2 are disposed between the reflective SLM 628-1 and the reflective SLM 628-2 and downstream of the reflective SLM 628-2. Note that a laser 662, a lens 664, and an aperture 666 are provided in front of the reflective SLM 628-1.

  In this way, when two stages of the reflection type SLM are used, the problem due to oblique reflection is further increased. That is, since the number of bending points increases, machining and optical adjustment become more difficult than when one reflective SLM is provided. Since the optical axis 650 is sandwiched between the optical axis 654 and the optical axis 652, it is particularly difficult to adjust the position of the optical device (lens 626-1) related to the optical axis 650.

In view of such circumstances, the present invention uses a reflective SLM, has high light energy utilization efficiency, is easy to design, assemble, and adjust the optical system, and can be downsized. An object of the present invention is to provide a spatial light modulation device, an optical processing device, and a method of using a coupling prism that can perform arbitrary optical processing.

In order to achieve the above object, the present invention provides a reflective spatial light modulator provided at a position shifted from a virtual reference straight line in a direction perpendicular to the virtual reference straight line, and the virtual reference straight line. An input-side reflective surface for reflecting incident light incident along the virtual reference line and making it incident obliquely as readout light on the reflective spatial light modulator; and provided on the virtual reference line An output-side reflecting surface for reflecting the readout light modulated and obliquely reflected by the reflective spatial light modulation element and outputting it as outgoing light along the virtual reference straight line, and comprising the reflective space The light modulation element includes an element reflection surface for reflecting the reading light from the input-side reflection surface, and the input-side reflection surface and the output-side reflection surface are separated by a distance L along the virtual reference line. Spaced apart and the element reflecting surface is The input reference reflection surface, the output reflection surface, and the element reflection surface are separated in a direction in which the virtual reference straight line extends from the virtual reference straight line by a distance h in a direction perpendicular to the virtual reference straight line. On the other hand, the elements are inclined by angles φ1, φ2, and φ3, the element reflection surface has a size c, and the input-side reflection surface is far from the reflection type spatial light modulation element with respect to the virtual reference line. And a size a2 on the side close to the reflective spatial light modulator, and the output-side reflecting surface is closer to the virtual reference line from the reflective spatial light modulator. B1 and a size b2 on the side far from the reflective spatial light modulation element, and the element reflection surface reflects the input side with respect to the optical axis of the incident light reflected by the input side reflection surface. A reflective space light having a size c1 on the side close to the surface; The modulation element modulates the reading light incident at a convergence angle in the range of 0 to α, emits the predetermined component at a divergence angle in the range of 0 to β, and enters the reflective spatial light modulation element. When the readout light is convergent light, α takes a positive value, and when it is divergent light, α takes a negative value, and the predetermined component of the readout light emitted from the reflective spatial light modulator is divergent light. In this case, β takes a positive value, and in the case of convergent light, β takes a negative value. The distances L and h and the angles φ1, φ2, and φ3 are expressed by the following equations (1) and ( 2), and the sizes c, c1, a1, a2, b1, and b2 satisfy the following expressions (3) to (8) with respect to α and β, and the predetermined component and Is a diffraction component having a diffraction order of 1 or more and n (n is a natural number greater than 0) or less, and α and β are the wavelength λ of the incident light and the reflective spatial light. Respect to the lattice constant d of the smallest grid pattern that can be displayed on the tone device provides a spatial light modulator that satisfies the following equation (9) and (10).

According to such a configuration, the input-side reflecting surface reflects incident light incident along the virtual reference straight line, and obliquely enters the reflective spatial light modulator as read light. The element reflection surface of the reflective spatial light modulation element reflects the read light from the input-side reflection surface obliquely. The output-side reflecting surface reflects the readout light modulated by the reflective spatial light modulator and reflected obliquely, and outputs it as outgoing light. At this time, the emitted light is output along a virtual reference straight line. Therefore, the principal ray of the incident light incident on the input side reflection surface of the spatial light modulator and the principal ray of the emission light emitted from the output side reflection surface are on the same virtual reference line. Therefore, the entire optical system can be made compact, and the design, assembly, and adjustment of the optical system are facilitated. Furthermore, any optical processing can be efficiently performed on any incident light by the reflective spatial light modulator. Moreover, according to such a structure, all the incident light which injects with the convergence angle of the range of 0- (alpha) with respect to an element reflective surface provided with the magnitude | size c is reflected by the input side reflective surface. All of the incident light reflected by the input-side reflecting surface is reflected by the element reflecting surface of the reflective spatial light modulator as reading light. Of the readout light reflected by the element reflecting surface and modulated by the reflective spatial light modulator, all the components emitted at a divergence angle in the range of 0 to β are reflected by the output side reflecting surface. It is possible to further increase the light use efficiency. In addition, it is ensured that the input side reflection surface and the output side reflection surface do not overlap. In particular, when the equal signs of the expressions (4) to (7) are established, a component having an angle larger than the divergence angle β can be removed as an unnecessary component. Further, according to such a configuration, it is ensured that all of the diffracted light of at least the first order and the nth order out of the modulated read light diffracted by the reflective spatial light modulator is reflected by the output side reflection surface. Is done. Accordingly, it is possible to further increase the light use efficiency. In particular, when the equal signs of the expressions (4) to (7) hold, diffracted light of (n + 1) th order or higher can be removed as an unnecessary component.

In order to achieve the above object, the present invention provides a reflective spatial light modulator provided at a position shifted from a virtual reference straight line in a direction perpendicular to the virtual reference straight line, and the virtual reference straight line. An input-side reflective surface for reflecting incident light incident along the virtual reference line and making it incident obliquely as readout light on the reflective spatial light modulator; and provided on the virtual reference line An output-side reflecting surface for reflecting the readout light modulated and obliquely reflected by the reflective spatial light modulation element and outputting it as outgoing light along the virtual reference straight line, and comprising the reflective space The light modulation element includes an element reflection surface for reflecting the reading light from the input-side reflection surface, and the input-side reflection surface and the output-side reflection surface are separated by a distance L along the virtual reference line. Spaced apart and the element reflecting surface is The input reference reflection surface, the output reflection surface, and the element reflection surface are separated in a direction in which the virtual reference straight line extends from the virtual reference straight line by a distance h in a direction perpendicular to the virtual reference straight line. On the other hand, they are inclined by angles φ1, φ2, and φ3, respectively, and a single coupling prism includes an input side transmission surface, a first reflection surface, a bonded transmission surface, a second reflection surface, and an output. A side transmission surface, and the input side transmission surface is provided on the virtual reference straight line, transmits incident light incident along the virtual reference straight line, and converts the incident light into the virtual reference straight line. The first reflection surface is provided on the virtual reference line, and reflects the incident light propagating through the virtual reference line from the input side transmission surface. The joint transmission surface is the virtual reference straight line or Provided at a position shifted in a direction perpendicular to the virtual reference straight line, joined to the reflective spatial light modulator, and transmits incident light reflected by the first reflecting surface and propagating inside. The reflected spatial light modulation element is incident obliquely as readout light, and the readout light modulated and reflected obliquely by the reflective spatial light modulation element is transmitted and propagated through the second spatial light modulation element. The reflective surface of the output side is provided on the virtual reference straight line, reflects the reading light propagating from the joint transmission surface, and propagates the inside as the outgoing light along the virtual reference straight line. The output side transmission surface is provided on the virtual reference line, and the outgoing light propagating through the second reflection surface along the virtual reference line is externally applied along the virtual reference line. Output to the coupling prize And the element reflecting surface has a size c, and the input side reflecting surface has a size a1 on the side far from the reflective spatial light modulator with respect to the virtual reference straight line, A size a2 on the side closer to the reflective spatial light modulator, and the output-side reflective surface is closer to the virtual reference straight line from the reflective spatial light modulator and the size b1 And b2 on the side far from the spatial light modulation element, and the element reflection surface is closer to the input reflection surface with respect to the optical axis of the incident light reflected by the input reflection surface. c1 and the reflective spatial light modulator modulates the reading light incident at a convergence angle in the range of 0 to α, and emits the predetermined component at a divergence angle in the range of 0 to β, When the readout light incident on the reflective spatial light modulator is convergent light, α takes a positive value and is divergent light. Α takes a negative value, β takes a positive value when the predetermined component of the readout light emitted from the reflective spatial light modulator is divergent light, and β takes a positive value when the light is convergent light. The distances L and h and the angles φ1, φ2, and φ3 satisfy the following expressions (1) and (2), and the magnitudes c, c1, a1, a2, b1, b2 satisfies the following expressions (3 ′) to (8 ′) with respect to α and β, and the predetermined component is a diffraction component having a diffraction order of 1 or more and n (n is a natural number greater than 0) or less. Where α and β are the following equations (9 ′) and (10) for the wavelength λ of the incident light and the lattice constant d of the smallest lattice pattern that can be displayed on the reflective spatial light modulator: A spatial light modulator characterized by satisfying ') is provided.

According to such a configuration, the input-side reflecting surface reflects incident light incident along the virtual reference straight line, and obliquely enters the reflective spatial light modulator as read light. The element reflection surface of the reflective spatial light modulation element reflects the read light from the input-side reflection surface obliquely. The output-side reflecting surface reflects the readout light modulated by the reflective spatial light modulator and reflected obliquely, and outputs it as outgoing light. At this time, the emitted light is output along a virtual reference straight line. Therefore, the principal ray of the incident light incident on the input side reflection surface of the spatial light modulator and the principal ray of the emission light emitted from the output side reflection surface are on the same virtual reference line. Therefore, the entire optical system can be made compact, and the design, assembly, and adjustment of the optical system are facilitated. Furthermore, any optical processing can be efficiently performed on any incident light by the reflective spatial light modulator. Further , according to such a configuration, the input side transmission surface transmits incident light incident along the virtual reference line and guides the incident light into the coupling prism along the virtual reference line. The first reflecting surface reflects incident light propagating from the input side transmitting surface along the virtual reference straight line. The bonded transmission surface bonded to the reflective spatial light modulator transmits the incident light reflected by the first reflective surface and propagates inside, and is incident obliquely as read light to the reflective spatial light modulator. In addition, the reading light modulated by the reflective spatial light modulator and reflected obliquely is transmitted and propagated inside. The second reflecting surface reflects the reading light propagating from the bonded transmission surface and propagates the inside along the virtual reference line as outgoing light. The output side transmission surface outputs outgoing light propagating from the second reflection surface along the virtual reference line to the outside along the virtual reference line. By using the coupling prism, the entire optical system can be made compact, and the design, assembly, and adjustment of the optical system are further facilitated. Further, according to such a configuration, all of the incident light incident at a convergence angle in the range of 0 to α with respect to the element reflection surface having the size c is reflected by the input side reflection surface, and the input side reflection surface. All of the reflected incident light is reflected as read light by the element reflection surface of the reflective spatial light modulation element, and is reflected by the element reflection surface and is modulated by the reflective spatial light modulation element. All components emitted from the reflective spatial light modulator with a divergence angle in the range of are reflected by the output-side reflecting surface. Therefore, it is possible to make all of the light incident on the entire element reflection surface, and it is possible to further improve the light use efficiency. In addition, it is ensured that the input side reflection surface and the output side reflection surface do not overlap. In particular, when the equal signs of the expressions (4 ′) to (7 ′) are established, a component having an angle larger than the divergence angle β can be removed as an unnecessary component. Further, according to such a configuration, it is ensured that all of the diffracted light of at least the first order and the nth order out of the modulated read light diffracted by the reflective spatial light modulator is reflected by the output side reflection surface. Is done. In particular, when the equal signs of equations (4 ′) to (7 ′) hold, diffracted light of (n + 1) th order or higher can be removed as an unnecessary component.

  Here, if each of the input-side reflection surface and the output-side reflection surface is set at a predetermined angle with respect to the virtual reference line, light can be totally reflected. Therefore, the light use efficiency is further improved. It is not necessary to perform surface processing or the like for increasing the reflectance of light on the input side reflection surface and the output side reflection surface.

In another aspect of the present invention, a spatial light modulator, an input optical system that is provided on the virtual reference line and that inputs incident light to the spatial light modulator along the virtual reference line, and the virtual An output optical system provided on a reference straight line for processing the emitted light output from the spatial light modulator along the virtual reference straight line, the spatial light modulator from the virtual reference straight line to the virtual A reflective spatial light modulator provided at a position shifted in a direction perpendicular to the reference straight line, and an incident incident on the virtual reference straight line and incident from the input optical system along the virtual reference straight line An input-side reflection surface for reflecting light to be incident on the reflective spatial light modulation element obliquely as read light, and provided on the virtual reference straight line, modulated by the reflective spatial light modulation element and obliquely Reflected reading An output-side reflecting surface for reflecting light and outputting it as outgoing light along the virtual reference straight line, and the reflective spatial light modulator reflects the readout light from the input-side reflecting surface The input-side reflection surface and the output-side reflection surface are separated by a distance L along the virtual reference line, and the element reflection surface is changed from the virtual reference line to the virtual reference line. The input side reflection surface, the output side reflection surface, and the element reflection surface are separated from each other in a direction perpendicular to the direction h by angles φ1, φ2 with respect to the direction in which the virtual reference straight line extends. , Φ3, the distances L, h, and the angles φ1, φ2, and φ3 satisfy the following expressions (1) and (2), and the input optical system performs Fourier transform on the input image. A reflective spatial light modulator having a first lens; Phase-modulates a Fourier transform image of the input image with a filter pattern based on a reference image, and the output optical system has a second lens for Fourier transforming the output light from the spatial light modulator, The image processing apparatus further includes an input image creating unit that outputs an image indicating a correlation between the input image and the reference image, and creates the input image, the input image creating unit including another spatial light modulation device, and the other space. The light modulation device includes a reflective spatial light modulator provided at a position shifted from the virtual reference straight line in a direction perpendicular to the virtual reference straight line, and the virtual spatial reference line provided on the virtual reference straight line. An input-side reflecting surface for reflecting incident light incident along the light source and causing the incident light to enter the reflective spatial light modulation element obliquely as readout light; and the reflective spatial light provided on the virtual reference straight line. An output-side reflecting surface for reflecting the readout light modulated by the modulation element and reflected obliquely and outputting it as the outgoing light along the virtual reference straight line, and the reflective spatial light modulation element comprises the input An element reflecting surface for reflecting the reading light from the side reflecting surface, and the input reflecting surface and the output reflecting surface are separated from each other by a distance L along the virtual reference straight line. Is spaced apart from the virtual reference line by a distance h in a direction perpendicular to the virtual reference line, and the virtual reference line extends from the input side reflection surface, the output side reflection surface, and the element reflection surface. The distances L, h, and the angles φ1, φ2, and φ3 satisfy the equations (1) and (2), respectively, with respect to the direction. 1 lens is output from the other spatial light modulator The emitted light provides an optical processing apparatus characterized by Fourier transform.

According to such a configuration, the input optical system and the output optical system are arranged on the virtual reference straight line. For this reason, it is possible to easily adjust the position of the entire optical processing apparatus simply by adjusting the positions of the input-side reflecting surface, the output-side reflecting surface, and the reflective spatial light modulator in the direction perpendicular to the virtual reference line. Can do. Therefore, the design, assembly, and adjustment of the optical system are simplified. According to such a configuration, the first lens performs Fourier transform on the input image. The reflective spatial light modulator modulates the phase of the Fourier transform image of the input image with a filter pattern based on the reference image. The second lens performs Fourier transform on the output light from the spatial light modulation device and outputs an image indicating the correlation between the input image and the reference image. Therefore, an image corresponding to the correlation between the input image and the reference image can be output using light efficiently. Further, according to such a configuration, the spatial light modulators are connected in multiple stages, and an input image can be freely generated while efficiently using light.

前記仮想基準直線に沿って第５の側面に向けて読み出し光を入射させ、前記カップリングプリズムの屈折率はｍであり、前記反射型空間光変調素子が、０〜αの範囲の収束角で入射する読みだし光を変調して、その所定の成分を０〜βの範囲の発散角で出射し、前記反射型空間光変調素子へ入射する読み出し光が収束光の場合にはαは正の値をとり発散光の場合にはαは負の値をとり、前記反射型空間光変調素子から出射する読み出し光の前記所定の成分が発散光の場合にはβは正の値をとり収束光の場合にはβは負の値をとり、前記所定の成分とは１以上ｎ（ｎは０より大きい自然数）以下の回折次数の回折成分であり、δはｎ次回折光の回折角度であり、α及びβが、前記入射光の波長λ、及び、前記反射型空間光変調素子に表示可能な最小の格子パターンの格子定数ｄに対して、以下の式（９´）及び（１０´）を満足することを特徴とする、カップリングプリズムの使用方法を提供している。

Further, in another aspect of the present invention, the first side surface and the second side surface are connected to each other at 90 ° in a pentagonal prism shape having the first to fifth side surfaces in this order, and the second side surface And the third side surface are connected to each other at 90 °, the third side surface and the fourth side surface are connected to each other at 90 ° -φ2, and the fourth side surface and the fifth side surface are connected to each other. A reflection type spatial light modulation element having an element reflection surface is prepared by connecting a 180 ° + φ1 + φ2 connection and preparing a coupling prism in which the fifth side and the first side are connected to each other at 90 ° -φ1. The element reflecting surface is joined to the second side surface so as to extend parallel to the second side surface, the virtual reference straight line penetrates the first side surface and the fifth side surface, and the fifth side surface and the fourth side surface A side surface is separated by a distance L along the virtual reference line, and the element reflection surface is in front of the virtual reference line. The fifth side surface, the fourth side surface, and the element reflecting surface are separated by a distance h in a direction perpendicular to the virtual reference line, and the angles φ1, φ2, The coupling prism is arranged with respect to the virtual reference line so that the inclination is φ3, the distances L and h, and the angles φ1, φ2, and φ3 satisfy the following expressions (1 ′) and (2 ′). ,

Read light is incident on the fifth side surface along the virtual reference straight line, the refractive index of the coupling prism is m, and the reflective spatial light modulator has a convergence angle in the range of 0 to α. The incident reading light is modulated, and the predetermined component is emitted with a divergence angle in the range of 0 to β. When the reading light incident on the reflective spatial light modulator is convergent light, α is positive. In the case of divergent light, α takes a negative value. In the case where the predetermined component of the readout light emitted from the reflective spatial light modulator is divergent light, β takes a positive value and converges light. In this case, β takes a negative value, the predetermined component is a diffraction component having a diffraction order of 1 or more and n (n is a natural number greater than 0) or less, δ is a diffraction angle of the n-order diffracted light, α and β are the wavelength λ of the incident light and the minimum displayable on the reflective spatial light modulator. Respect to the lattice constant d of child patterns, characterized by satisfying the following equation (9 ') and (10'), provides the use of a coupling prism.

According to such a method, the first side surface transmits incident light incident along the virtual reference straight line and guides the incident light into the coupling prism. The fifth side surface reflects light propagating from the first side surface. The second side surface joined to the reflective spatial light modulation element transmits the light reflected by the fifth lateral surface and propagates inside, and is incident obliquely as read light on the reflective spatial light modulation element. In addition, the reading light modulated by the reflective spatial light modulator and reflected obliquely is transmitted and propagated inside. The fourth side surface reflects the reading light propagating from the second side surface and propagates the inside as outgoing light. The third side surface outputs the outgoing light propagating from the fourth side surface to the outside along the virtual reference straight line. Therefore, the chief ray of incident light incident on the first side surface of the coupling prism and the chief ray of outgoing light emitted from the third side surface are on the same virtual reference line. By using the coupling prism, the entire optical system can be made compact, and the design, assembly, and adjustment of the optical system are facilitated. Furthermore, any optical processing can be efficiently performed on any incident light by the reflective spatial light modulator. In addition, it is ensured that all of the diffracted light of at least the first order and the nth order out of the modulated read light diffracted by the reflective spatial light modulator is reflected by the fourth side surface. In particular, when the equal signs of equations (4 ′) to (7 ′) hold, diffracted light of (n + 1) th order or higher can be removed as an unnecessary component.

These are figures which show the structure of the conventional optical processing apparatus (pattern formation optical system). These are figures which show the structure of another conventional optical processing apparatus (4f optical system). These are figures which show the structure of the 4f optical system obtained by improving the 4f optical system of FIG. FIG. 4 is a diagram for explaining a problem that occurs in the position adjustment of the reflective SLM in the optical processing apparatus of FIG. 3; These are figures which show the structure of another 4f optical system obtained by applying the 4f optical system of FIG. These are figures which show the structure of the spatial light modulation apparatus concerning 1st Embodiment. These are figures which show the structure of the reflection type SLM provided in the spatial light modulation apparatus concerning 1st Embodiment. These are the figures which show the positional relationship of the chief ray of the read-out light, reflection type | mold SLM, and two mirrors in the spatial light modulation apparatus of FIG. These are figures which show the state in which the read-out light in the spatial light modulation apparatus of FIG. 6 is reflected. These are figures which show the state in which the principal ray and edge ray of an input light beam are reflected in the input side reflective surface in the spatial light modulation device of FIG. These are figures which show the state in which the principal ray and edge ray of an output light beam are reflected in the output side reflective surface in the spatial light modulation apparatus of FIG. These are the linear optical path diagrams which developed the reflection in each reflective surface in the spatial light modulation device of FIG. These are figures which show the structure of the optical processing apparatus (4f optical system) which employ | adopted the spatial light modulation apparatus of FIG. FIG. 14 is a diagram for explaining position adjustment of the reflective SLM in the optical processing apparatus of FIG. 13; These are figures which show the structure of the spatial light modulation apparatus concerning 2nd Embodiment. These are figures which show the structure of the optical processing apparatus (waveform shaping optical system) which employ | adopted the spatial light modulation apparatus of FIG. These are figures which show the structure of another optical processing apparatus (4f optical system) which employ | adopted the spatial light modulation apparatus of FIG. These are figures which show the structure of another optical processing apparatus (4f optical system) which employ | adopted the spatial light modulation apparatus of FIG. These are figures which show the structure of another optical processing apparatus (wavefront compensation optical system) which employ | adopted the spatial light modulation apparatus of FIG. These are figures which show the structure of the spatial light modulation apparatus concerning 3rd Embodiment. These are figures which show the structure of the spatial light modulation apparatus concerning 4th Embodiment. These are figures which show the positional relationship of reflective SLM, the input side reflective surface, and the output side reflective surface in the spatial light modulation apparatus which concerns on the example of a change.

Explanation of symbols

1 Spatial Light Modulator 3 Mirror 5 Reflective SLM
5c Element reflecting surface 7 Mirror 9 Virtual reference line 30 Spatial light modulator 32 Prism 40 Spatial light modulator 42 Prism 50 Spatial light modulator 52 Coupling prism 60 Optical processor 62 Laser 80 Optical processor 81 Light source 82 Collimating lens 84 Input Surface 86 Fourier transform lens 88 Fourier transform lens 90 Output surface 91 Optical axis 92 Optical axis 100 Optical processing device 200 Optical processing device 300 Optical processing device 302 Input surface 312 Beam sampler 314 Wavefront sensor 316 Control device 318 Output surface M1 Input side reflection surface M2 Output side reflection surface P1 Input side transmission surface P2 Bonding transmission surface P3 Output side transmission surface I Input optical system O Output optical system R Parallel light projection optical system

The spatial light modulator according to an embodiment of the present invention, the optical processing equipment, and, for the use of the coupling prism, will be described with reference to the accompanying drawings.

  The spatial light modulation device 1 according to the first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 6, the spatial light modulation device 1 according to the first embodiment includes a mirror 3, a reflective spatial light modulation element 5 (hereinafter referred to as a reflective SLM 5), and a mirror 7.

  The reflective SLM 5 is disposed at a position shifted from the predetermined virtual reference line 9 in a direction perpendicular to the virtual reference line 9. The reflective SLM 5 includes a modulation unit 5a, a mirror layer 5b, and an address unit 5d. The surface on the modulation unit 5a side of the mirror layer 5b defines the element reflection surface 5c. The reflection type SLM 5 is arranged so that the modulation unit 5 a faces the virtual reference straight line 9.

  Both the mirrors 3 and 7 are arranged on the virtual reference straight line 9. The mirrors 3 and 7 are both arranged obliquely with respect to the virtual reference straight line 9. More specifically, the mirrors 3 and 7 are arranged in a “C” shape on the virtual reference straight line 9. The mirror 3 has an input side reflection surface M1, and the mirror 7 has an output side reflection surface M2. Read light enters the input side reflection surface M1 as an input beam along a virtual reference line 9 from an input side optical system (not shown). That is, the principal ray (optical axis) 11 of the input beam travels along the virtual reference line 9. The input-side reflection surface M1 reflects the readout light to the reflection type SLM5. The readout light that has entered the reflection type SLM 5 is modulated when propagating through the modulation unit 5 a, reflected by the element reflection surface 5 c, propagated again through the modulation unit 5 a, further modulated, and then emitted from the reflection type SLM 5. The readout light is reflected by the output-side reflecting surface M2, travels along the virtual reference line 9 as an output beam, is emitted from the spatial light modulator 1, and is output to an output-side optical system (not shown). In this way, the principal ray (optical axis) 17 of the output beam also travels along the virtual reference line 9. A path along which the input beam principal ray 11 and the output beam principal ray 17 pass is defined as an optical axis in the spatial light modulator 1. Further, the change in the optical axis of the readout light due to the reflection on the input side reflection surface M1, the reflection type SLM5, and the output side reflection surface M2 all occurs in the paper surface of FIG. 6, and the optical axis in the direction perpendicular to the paper surface is changed. It is assumed that there is no change in angle.

  When the reflective SLM 5 is, for example, a parallel-aligned nematic liquid crystal spatial light modulator (Parallel-Aligned nematic-Liquid-Crystal Spatial Light Modulator: hereinafter referred to as PAL-SLM), it is shown in FIG. As described above, the modulation unit 5 a includes the horizontally aligned nematic liquid crystal layer 500, the transparent electrode 501, and the transparent substrate 502. The mirror layer 5b is composed of a multilayer dielectric layer 503. The surface of the multilayer dielectric layer 503 on the liquid crystal layer 500 side defines the element reflecting surface 5c. The address portion 5 d is composed of a photoconductive layer 504, a transparent electrode 505, and a transparent substrate 506. When intensity modulated light having a desired intensity distribution is applied to the photoconductive layer 504 through the transparent substrate 506 and the transparent electrode 505, the refractive index distribution of the liquid crystal layer 500 changes. The readout light enters the liquid crystal layer 500 via the transparent substrate 502 and the transparent electrode 501, is phase-modulated by the liquid crystal layer 500, and is reflected by the multilayer dielectric layer 503. Thus, the readout light is converted into phase-modulated light having a phase distribution corresponding to a desired intensity distribution and is emitted from the reflective SLM 5. In this case, the liquid crystal layer 500 can modulate only the phase of the readout light.

  For example, as shown in FIG. 7, a relay lens 540, a liquid crystal display (hereinafter referred to as an LCD) 530, a collimating lens 520, and a writing light source 510 may be arranged facing the address part 5d of the reflective SLM 5. good. The writing light source 510 emits writing light having a uniform intensity distribution. The collimating lens 520 converts writing light into parallel light. The LCD 530 is a transmission type electric address type intensity modulation type spatial light modulator. The LCD 530 is electrically addressed by a signal input from a control unit (not shown), and converts the incident parallel light into intensity modulated light having a desired intensity distribution. The relay lens 540 forms an image of the intensity modulated light on the reflective SLM 5.

  Note that the reflective SLM 5, the writing light source 510, the collimating lens 520, the LCD 530, and the relay lens 540 may be housed in a housing and configured as the phase modulation module 6. In this case, by arranging the phase modulation module 6 with respect to the mirrors 3 and 7 as shown in FIG. 7, the positional relationship between the reflective SLM 5 and the mirrors 3 and 7 is the same as that described with reference to FIG. can do.

  As the phase modulation module 6, for example, an electric address type liquid crystal phase modulation module “SLMX7550” (trade name, manufactured by Hamamatsu Photonics Co., Ltd.) can be used.

  Next, a specific arrangement relationship among the input-side reflection surface M1, the element reflection surface 5c, and the output-side reflection surface M2 will be described with reference to FIG. In FIG. 8, for the sake of clarity, only the mirror layer 5b of the reflective SLM 5 is shown, and the modulation unit 5a and the address unit 5d are not shown.

  As shown in FIG. 8, the point where the input principal ray 11 is incident on the input side reflection surface M1 is the point A, the point where the principal ray of the light reflected by the input side reflection surface M1 is incident on the reflection type SLM 5 is the reflection point A point B is a point where a principal ray of light modulated by the mold SLM 5 and reflected by the element reflection surface 5c is incident on the output-side reflection surface M2. A straight line AB connecting the point A and the point B is located on the virtual reference straight line 9. The input-side reflecting surface M1 extends in a direction that forms an angle φ1 with respect to the virtual reference straight line 9. The output-side reflecting surface M2 extends in a direction that forms an angle φ2 with respect to the virtual reference straight line 9. The element reflecting surface 5c extends in a direction that forms an angle φ3 with respect to the virtual reference straight line 9. Note that φ1 and φ3 take positive values in the counterclockwise direction from the virtual reference line 9 in FIG. Further, φ2 takes a positive value in the clockwise direction from the virtual reference straight line 9 in FIG. φ1 and φ2 satisfy 0 ° <φ1 <90 ° and 0 ° <φ2 <90 °. That is, the input side reflection surface M1 and the output side reflection surface M2 extend obliquely with respect to the virtual reference line 9. The element reflecting surface 5c extends obliquely or parallel to the virtual reference straight line 9. In addition, both ends of the input-side reflection surface M1 are point A1 and point A2. Of the points A1 and A2, the point A2 is located on the reflective SLM 5 side with respect to the virtual reference straight line 9. The point A1 is located on the opposite side of the reflective SLM 5 from the virtual reference line 9. The length of the line segment A1-A2 is a, the length of the line segment A-A1 is a1, and the length of the line segment A-A2 is a2. Both ends of the output-side reflecting surface M2 are defined as point B1 and point B2. Of the points B1 and B2, the point B1 is located on the reflective SLM 5 side from the virtual reference line 9, and the point B2 is located on the opposite side of the reflective type SLM 5 from the virtual reference line 9. The length of the line segment B1-B2 is b, the length of the line segment B-B1 is b1, and the length of the line segment B-B2 is b2. Two end points of the element reflecting surface 5c are defined as a point C1 and a point C2. The point C1 is located closer to the input reflecting surface M1 than the output reflecting surface M2, and the point C2 is located closer to the output reflecting surface M2 than the input reflecting surface M1. The length of the line segment C1-C2 (that is, the effective aperture of the reflective SLM 5) is c, the length of the line segment C-C1 is c1, and the length of the line segment C-C2 is c2. Further, a perpendicular foot from the point C to the line segment AB is a point D, a length of the perpendicular line CD is h, and a length of the line segment AB is L.

及び

In the present embodiment, the angles φ1, φ2, and φ3 and the lengths L and h have the following relationships (1) and (2).

as well as

  Since the above relations (1) and (2) are satisfied, the input principal ray 11 incident on the input side reflection surface M1 not only travels along the virtual reference line 9, but also the output principal reflected by the output side reflection surface M2. It is ensured that the ray 17 also travels along the virtual reference line 9. In other words, it is ensured that the output principal ray 17 is located on the extension line of the input principal ray 11 (condition 1).

  Here, as shown in FIG. 9, it is assumed that readout light (input light beam) is incident along a virtual reference line 9 from a not-shown input optical system at a convergence angle in the range of 0 to α. . Note that α takes a positive value when the input light beam is convergent light, and α takes a negative value when the input light beam is divergent light. Further, it is assumed that the beam diameter when the reading light (input light beam) is incident on the reflection type SLM 5 is equal to the length c of the element reflection surface 5c. Further, the readout light modulated by the reflective SLM 5 and reflected by the element reflective surface 5 c is emitted from the reflective SLM 5. It is assumed that a desired component (that is, a desired component desired to be output from the spatial light modulator 1) out of the readout light is emitted as an output light beam at a divergence angle in the range of 0 to β. Note that β takes a positive value when the output light beam is divergent light, and β takes a negative value when the output light beam is convergent light. It is assumed that the absolute values of α and β are sufficiently small, and the change in the cross-sectional shape of the light beam due to the light condensing / diverging near the reflective SLM 5 can be ignored. Therefore, the length of the input light beam along the element reflection surface 5c near the element reflection surface 5c is not only substantially equal to the length c of the element reflection surface 5c, but also the element near the element reflection surface 5c of the output light beam. It is assumed that the length along the reflection surface 5c is substantially equal to the length c of the element reflection surface 5c. In FIG. 9, as in FIG. 8, for the sake of clarity, only the mirror layer 5b is shown in the reflective SLM 5, and the modulation unit 5a and the address unit 5d are not shown.

In the present embodiment, the angles φ1, φ2 and the lengths c, c1, h, a1, a2, b1, b2, L (FIG. 8) have the following relationship with respect to the convergence angle α and the divergence angle β. (3) to (8).

  Here, the light rays defining the outermost part of the input light beam are referred to as input edge light rays 13 and 15. The input marginal rays 13 and 15 propagate in a direction that forms a convergence angle α with respect to the input principal ray 11. Since the input light is symmetric with respect to the input principal ray 11 (optical axis), the intensity of the input marginal rays 13 and 15 is equal to each other. That is, the intensity of the input marginal rays 13 and 15 is a predetermined ratio of the intensity of the input principal ray 11. Further, the light rays defining the outermost part of the output light beam are referred to as output edge light rays 19 and 21. The output light beam is symmetric with respect to the output chief ray 17 (optical axis). The output marginal rays 19 and 21 propagate in a direction that forms a divergence angle β with respect to the output principal ray 17.

  In the present embodiment, since Expressions (3) to (8) are satisfied, as shown in FIG. 10, the input principal ray 11 is reflected at a point A on the mirror 3 to be a point of the reflective SLM 5. C. The input marginal ray 13 is reflected at another point on the mirror 3 (a point between the end points A1 and A) and reaches one end C1 of the element reflection surface 5c of the reflective SLM 5. The other input edge ray 15 is reflected at yet another point on the mirror 3 (a point between the end point A2 and the point A) and reaches the other end C2 of the element reflection surface 5c of the reflection type SLM5. Thus, the entire input light beam is reflected by the mirror 3 to reach the reflection type SLM 5 and is modulated by the reflection type SLM 5.

  Further, as shown in FIG. 11, the output principal ray 17 is reflected at a point B on the mirror 7. The output edge ray 19 is emitted from one end C1 of the element reflection surface 5c of the SLM 5 and reflected at a point on the mirror 7 (a point between the end point B1 and the point B). The other output edge ray 21 is reflected at another point on the mirror 7 (a point between the end point B2 and the point B). In this way, the entire output light beam of the desired component output from the reflective SLM 5 is reflected by the mirror 7 and guided to an output side optical system (not shown).

  Therefore, as shown in FIG. 9, all of the input beams from the input side optical system are reflected by the input side reflection surface M1 (condition 2), and all of the beams reflected by the input side reflection surface M1 are reflected on the reflection type SLM5. It is ensured that all necessary components of the beam incident (condition 3) and modulated and reflected by the reflective SLM 5 are reflected by the output-side reflecting surface M2 (condition 4). Further, the expression (8) ensures that the positions of the input-side reflecting surface M1 and the output-side reflecting surface M2 do not overlap.

Here, the following relationship (9) exists between the convergence angle α of the input light beam and the divergence angle β of the output light beam, as shown in FIG. FIG. 12 is a straight optical path diagram in which reflection on each of the input side reflection surface M1, the element reflection surface 5c, and the output side reflection surface M2 is developed.

For example, when it is desired to output from the spatial light modulator 1 diffracted light up to n-th order diffracted light (where n is a natural number of 1 or more) among diffracted light generated by being modulated by the reflective SLM 5, δ is n This is the diffraction angle of the next diffracted light. The diffraction angle δ of the nth order diffracted light is given by the following equation (10).

  Here, d is the lattice constant of the smallest lattice pattern that can be displayed on the reflective SLM 5 (the distance between the centers of adjacent stripes), and λ is the wavelength of the readout light.

  Accordingly, the parameters φ1, φ2, c, c1, h, a1, a2, b1, b2, and L are expressed by the formulas (1) to (1) with respect to the convergence angle α of the input light incident from the input optical system and the desired diffraction order n. If the selection is made so as to satisfy 10), the reflection light SLM 5 can be effectively irradiated with the input light. Furthermore, 1-n order diffracted light obtained by the reflective SLM 5 can be effectively output from the spatial light modulator 1.

For example, when it is desired to output first-order or lower-order diffracted light from the spatial light modulator 1, α is set to the convergence angle of input light incident from the input optical system, the diffraction order n is set to n = 1, The parameters φ1, φ2, c, c1, h, a1, a2, b1, b2, and L may be selected so as to satisfy the equations (1) to (10). Further, when it is desired to output the first-order diffracted light and the second-order diffracted light from the spatial light modulator 1, the diffraction order n may be reset to n = 2.
In particular, if the parameters φ1, φ2, c, c1, h, a1, a2, b1, b2, and L are selected so that the equal sign is established in the equations (4) to (7), the 1st to nth order diffracted light is effective. (N + 1) th order or higher unnecessary diffracted light can be removed.

  As described above, according to the spatial light modulation device 1 of the present embodiment, the input principal ray 11 and the output principal ray 17 both travel along the virtual reference straight line 9, so that the input side with respect to the spatial light modulation device 1 is the input side. When combining the optical system and the output side optical system, both the input side optical system and the output side optical system can be arranged on the virtual reference line 9. Therefore, the design, assembly, and position adjustment of the entire optical system are extremely easy, and the entire optical system can be made compact. A plurality of spatial light modulators 1 can be connected in multiple stages along a single virtual reference line 9. Further, the reflective SLM 5 can perform arbitrary modulation on an arbitrary input light beam and can perform arbitrary optical processing. In addition, since the input-side reflecting surface M1 is configured by the mirror 3 and the output-side reflecting surface is configured by the mirror 7, the overall configuration of the spatial light modulator 1 is simplified.

  Since the length of the mirrors 3 and 7 is determined according to the length c (effective area) of the reflective SLM 5, the entire spatial light modulator 1 can be manufactured easily and inexpensively. This is because the reflective SLM 5 is difficult and expensive to manufacture compared to the mirrors 3 and 7, whereas the mirrors 3 and 7 are easy to manufacture and inexpensive.

  In addition, all of the incident light on the input-side reflecting surface M1 is reflected by the input-side reflecting surface M1, and all of the incident light reflected by the input-side reflecting surface M1 is incident on the reflective SLM 5 as readout light and further reflected. All the desired components of the readout light modulated by the mold SLM5 are reflected by the output side reflection surface M2. Therefore, the light utilization efficiency can be increased, and the advantages of the reflective SLM 5 having a high effective aperture ratio can be utilized.

In particular, when φ3 is zero (0), that is, when the element reflection surface 5c is parallel to the virtual reference line 9, a1 = b2 and a2 = b1 in FIG. Therefore, if one of the parameters of either a1 and a2 or b1 and b2 is determined, the other set is automatically determined. When α> β, a1 and a2 may be considered, and when β> α, b1 and b2 may be considered. Now, assuming that β> α, the equations (1) to (8) can be rewritten as the following (11) to (16).

  The parameters φ1, φ2, c, c1, h, a1, a2, b1, b2, and L are expressed by equations (11) to (16) with respect to the convergence angle α of the input beam incident from the input optical system and the desired value β. Is selected, the output principal ray 17 is on the extension of the input principal ray 11 (condition 1), and all of the input beam to the input side reflection surface M1 is reflected by the input side reflection surface M1 (conditions). 2) All of the beams reflected by the input side reflection surface M1 are incident on the reflection type SLM 5 (Condition 3), and all necessary components of the beam modulated by the reflection type SLM 5 are reflected by the output side reflection surface M2. (Condition 4) is ensured. Since the element reflecting surface 5c is parallel to the virtual reference straight line 9, the design, assembly, and adjustment of the optical system become easier.

  Note that the input-side optical system (not shown) includes, for example, a pinhole (aperture) and a lens so that the readout light (input light beam) has a convergence angle in the range of 0 to α and the element reflection surface 5c. It is possible to ensure that the light beam is incident on the reflective SLM 5 with a beam diameter c equal to the length c. In this case, the input edge rays 13 and 15 are rays that have passed through the edge of the pinhole.

  Consider a case where an input-side optical system (not shown) makes readout light (input light beam) incident on the spatial light modulator 1 at an arbitrary convergence angle and an arbitrary beam diameter. Also in this case, the positional relationship between the input-side reflecting surface M1, the output-side reflecting surface M2, and the element reflecting surface 5c should be set so as to satisfy the equations (1) to (8) or the equations (11) to (16). Thus, all of the components of the readout light incident on the input-side reflecting surface M1 that propagate in the direction that forms an angle of 0 to α with respect to the principal ray 11 and enter the element reflecting surface 5c of the reflective SLM 5 are input-side. All of the readout light reflected by the reflective surface M1 and reflected by the input-side reflective surface M1 is incident on the reflective SLM 5, modulated by the reflective SLM 5, and emitted from the reflective SLM 5 at an angle of 0 to β. It can be ensured that all desired components are reflected by the output-side reflecting surface M2.

  Next, an optical processing device 80 that employs the spatial light modulation device 1 will be described with reference to FIGS. 13 and 14.

  As shown in FIG. 13, the optical processing device 80 includes a light source 81, a pinhole 83, a collimating lens 82, an input surface 84, a Fourier transform lens 86, a spatial light modulator 1, a Fourier transform lens 88, and an output surface 90. I have. The optical processing device 80 is a 4f optical system (Fourier transform optical system) that outputs a pattern indicating a correlation between an input image displayed on the input surface 84 and a reference image displayed on the reflective SLM 5. The light source 81, the pinhole 83, the collimating lens 82, and the input surface 84 constitute the input optical system I. Among these, the light source 81, the pinhole 83, and the collimating lens 82 constitute a parallel light projecting optical system R. The Fourier transform lens 88 and the output surface 90 constitute an output optical system O.

  The spatial light modulation device 1 includes mirrors 3 and 7 and a reflective SLM 5. The reflective SLM 5 is, for example, the PAL-SLM described with reference to FIG. 7, and is also incorporated in the phase modulation module 6 described with reference to FIG. In FIG. 13, only the reflective SLM 5 is shown for the sake of clarity.

  The light source 81, the pinhole 83, the collimator lens 82, the input surface 84, the Fourier transform lens 86, the Fourier transform lens 88, the output surface 90, the mirror 3, and the mirror 7 are disposed on the virtual reference straight line 9. The distance between the input surface 84 and the Fourier transform lens 86 and the distance through the mirror 3 between the Fourier transform lens 86 and the element reflection surface 5c are the focal length (length f1) of the Fourier transform lens 86. Are set equal. The distance through the mirror 7 between the element reflecting surface 5c and the Fourier transform lens 88 and the distance between the Fourier transform lens 88 and the output surface 90 are the focal length (length f2) of the Fourier transform lens 88. Are set equal. The light source 81 is a laser, and emits linearly polarized light having a predetermined wavelength as readout light. The pinhole 83 and the collimating lens 82 convert the readout light into parallel light having a predetermined beam diameter. Accordingly, parallel light having a predetermined beam diameter is projected onto the input surface 84. A device that changes the light intensity and / or phase of the projected parallel light according to the input image (for example, a transmissive object such as a film or a mask that displays the input image) is disposed on the input surface 84. Yes. The input light (input image) modulated by the input surface 84 is Fourier transformed by the Fourier transform lens 86 and enters the reflective SLM 5 via the mirror 3. At this time, the input light is incident on the reflective SLM 5 at the convergence angle α and the beam diameter c. The reflective SLM 5 displays a filter pattern created based on the reference image, and modulates and outputs the input image incident on the reflective SLM 5. The output light is reflected by the mirror 7 and propagates along the virtual reference straight line 9, is Fourier transformed by the Fourier transform lens 88, and outputs a correlation pattern on the output surface 90.

  In the spatial light modulation device 1, the reflective SLM 5 is arranged at a position shifted from the virtual reference line 9 in a direction perpendicular to the virtual reference line 9. The element reflection surface 5 c of the reflective SLM 5 is arranged in parallel to the virtual reference line 9. That is, the reflective SLM 5 is arranged so that φ3 = 0 (FIG. 8). The mirrors 3 and 7 and the reflective SLM 5 satisfy the expressions (11) to (16) and (9) and (10) with respect to the convergence angle α of the input light beam and the desired maximum diffraction order n. Is arranged.

  According to the optical processing device 80, all of the input light output from the input optical system I is incident on the mirror 3, and all components of the light reflected by the mirror 3 are incident on the reflective SLM 5, and are modulated by the reflective SLM 5. All necessary components (1st to n-th order diffracted light) of the reflected light are reflected by the mirror 7 and Fourier transformed by the Fourier transform lens 88. Therefore, the light utilization efficiency can be increased, and the advantages of the reflective SLM 5 having a high effective aperture ratio can be utilized.

  Further, the input optical system I and the output optical system O are disposed on the virtual reference line 9, and both the optical axis 91 of the input light and the optical axis 92 of the output light are positioned on the virtual reference line 9. Yes. The reflection type SLM 5 is at a position shifted from the virtual reference line 9 in the vertical direction. Further, the light source 81, the pinhole 83, the collimating lens 82, the input surface 84, the Fourier transform lens 86, the Fourier transform lens 88, and the output surface 90 are all the virtual reference straight line 9 with respect to the virtual reference straight line 9. It is arranged in a direction penetrating perpendicularly. As described above, the input optical system I, the output optical system O, and the reflective SLM 5 are arranged in a parallel or perpendicular direction with respect to the single virtual reference straight line 9. Since the housing of the reflective SLM 5 is generally a rectangular parallelepiped, the reflective SLM 5 is easily aligned with the input optical system and the output optical system, and the entire optical processing apparatus 80 can be easily designed in a compact manner. Further, when the entire optical processing apparatus 80 is provided on the substrate, the single virtual reference straight line 9 may be set on the substrate, so that machining is facilitated. This facilitates the design and assembly of the optical system.

  Since the element reflection surface 5c of the reflective SLM 5 is arranged so as to be parallel to the virtual reference line 9, a line parallel to the virtual reference line 9 can be used as a reference for the position of the element reflection surface 5c. The design and assembly of the optical system is easier. Further, since the input optical system I and the output optical system O are separated from the reflective SLM 5, the optical adjustment of the input optical system I and the output optical system O may be performed on the virtual reference line 9. In addition, since the input surface 84, the Fourier transform lens 86, the Fourier transform lens 88, and the output surface 90 are arranged in a direction in which the virtual reference straight line 9 passes through the virtual reference straight line 9 perpendicularly to the virtual reference straight line 9, Parallel lines and vertical lines with respect to the straight line 9 can be used for optical adjustment. Therefore, optical adjustment is also easy.

  Hereinafter, this optical adjustment will be specifically described with reference to FIG.

  For example, in order to change the position of the reflective SLM 5 in the optical axis direction, the reflective SLM 5 is moved from a position I indicated by a solid line to a position II indicated by a broken line. At the same time, the mirror 3 and the mirror 7 are also moved from a position indicated by a solid line to a position indicated by a broken line in a direction perpendicular to the virtual reference straight line 9. If the positional relationship between the reflective SLM 5 and the mirrors 3 and 7 continues to satisfy Expression (12) both before and after movement (solid line) and after movement (broken line), the optical axis 91 of the input light and the optical axis 92 of the output light Continues to be positioned on the virtual reference line 9. However, the lengths of a1, a2, b1, b2, etc. are set longer in consideration of the margin for adjustment in advance, and the inequalities of equations (14) to (16) continue to be satisfied even after movement. Suppose that

  The triangle ACB formed by the optical path A-C-B before movement and the triangle A'C'B 'formed by the optical path A'-C'-B' after movement are similar to each other. Let the length of the line segment AB be the length L, the point where the perpendicular drawn from the point C to the line segment AB intersects the line segment AB is the point D, and the length of the line segment CD is the length h. Now, it is assumed that the side length of the triangle A′C′B ′ is w times larger than the triangle ACB. That is, it is assumed that the distance between the virtual reference straight line 9 and the reflective SLM 5 is increased by w times before and after the movement.

  The optical path length from the mirror 3 before the movement to the reflective SLM 5 is A′A + AC, and after the movement is the length A′C ′. The length A′A is (w−1) h / tan (2φ1), the length AC is h / sin (2φ1), and the length A′C ′ is wAC. Since the change d of the optical path length before and after the movement can be calculated by A′C ′ − (A′A + AC), it is expressed by d = (w−1) htan (φ1). When the movement amount of the reflection type SLM 5 and the mirrors 3 and 7 in the direction perpendicular to the virtual reference line 9 is Δh, Δh = (w−1) h = d / tan (φ1).

  As described above, the position adjustment of the reflection type SLM 5 performed for adjusting the optical path length can be easily realized by moving the reflection type SLM 5 and the mirrors 3 and 7 in the direction perpendicular to the virtual reference straight line 9. It is not necessary to move the optical axes 91 and 92 related to the optical devices of the optical system I and the output optical system O. Therefore, the position adjustment in the optical axis direction of the optical devices of the input optical system I and the output optical system O and the position adjustment in the direction perpendicular to the optical axes of the reflective SLM 5 and the two mirrors 3 and 7 are performed independently of each other. be able to.

  In the optical processing apparatus 80, φ3 may not be zero (0). That is, the element reflection surface 5 c of the reflective SLM 5 may not be parallel to the virtual reference line 9. In this case, the mirrors 3 and 7 and the reflective SLM 5 may be arranged so as to satisfy the equations (1) to (8) instead of the equations (11) to (16). Even if the angle φ3 formed by the reflective SLM 5 and the virtual reference straight line 9 is not zero, the reflective SLM 5 and the mirrors 3 and 7 are perpendicular to the virtual reference straight line 9 as described with reference to FIG. The optical path length can be adjusted simply by moving in any direction.

  Next, a spatial light modulation device 30 according to the second embodiment will be described with reference to FIG.

  The spatial light modulation device 30 is the same as the spatial light modulation device 1 according to the first embodiment except that a prism 32 is provided instead of the mirrors 3 and 7. Accordingly, the spatial light modulation device 30 includes the reflective SLM 5 and the prism 32. In FIG. 15, members having the same functions and configurations as those of the spatial light modulator 1 are denoted by the same reference numerals. For the sake of clarity, only the mirror layer 5b of the reflective SLM 5 is shown, and the modulation unit 5a and the address unit 5d are not shown. The reflective SLM 5 is, for example, the PAL-SLM described with reference to FIG. 7, and may be incorporated in the phase modulation module 6 (FIG. 7).

  The prism 32 is a triangular prism having a triangular cross section. Of the three surfaces S1, S2, and S3 (outer surface) constituting the triangular prism, two surfaces S1 and S2 are subjected to processing for increasing the reflectance. These two surfaces S1 and S2 function as an input side reflection surface M1 and an output side reflection surface M2, respectively. In the prism 32, the input-side reflection surface M 1 and the output-side reflection surface M 2 are positioned on the virtual reference line 9, and the remaining one surface S 3 is shifted from the virtual reference line 9 in a direction perpendicular to the virtual reference line 9. It is arrange | positioned so that it may be located in the position.

  The input-side reflecting surface M1 reflects input light incident along the virtual reference straight line 9 to the reflective SLM 5. The reflective SLM 5 modulates and reflects the input light reflected by the input side reflection surface M1. The output-side reflection surface M2 reflects the light from the reflective SLM 5 and outputs it along the virtual reference line 9.

  The arrangement relationship among the input-side reflecting surface M1, the output-side reflecting surface M2, and the element reflecting surface 5c is the same as that shown in FIG. 10, except that the end point A2 of the input-side reflecting surface M1 and the end point B1 of the output-side reflecting surface M2 match. 8 is the same as the positional relationship among the input side reflection surface M1, the output side reflection surface M2, and the element reflection surface 5c in the first embodiment described with reference to FIG.

  That is, as shown in FIG. 15, a point where the input chief ray 11 is incident on the input side reflecting surface M1 is a point A, and a point where the chief ray of the light reflected by the input side reflecting surface M1 is incident on the reflective SLM 5 is a point C. A point B is a point where a principal ray of light modulated by the reflective SLM 5 and reflected by the element reflection surface 5c is incident on the output-side reflection surface M2. A straight line AB connecting the point A and the point B is located on the virtual reference straight line 9. The angle formed between the input side reflection surface M1 and the virtual reference line 9 is φ1, the angle formed between the output side reflection surface M2 and the virtual reference line 9 is φ2, and the angle formed between the element reflection surface 5c and the virtual reference line 9 is φ3. Define. Note that φ1 and φ3 take positive values counterclockwise from the virtual reference line 9 in FIG. In FIG. 15, φ2 takes a positive value in the clockwise direction from the virtual reference straight line 9. φ1 and φ2 satisfy 0 ° <φ1 <90 ° and 0 ° <φ2 <90 °. In addition, with respect to the points A1 and A2 at both ends of the input side reflection surface M1, the length of the line segment A1-A2 is a, the length of the line segment A-A1 is a1, and the length of the line segment A-A2 is Let a2. The length of the line segment B1-B2 is b, the length of the line segment B-B1 is b1, and the length of the line segment B-B2 is b2 with respect to the points B1 and B2 at both ends of the output-side reflecting surface M2. To do. For the two end points C1 and C2 of the element reflecting surface 5c, the length of the line segment C1-C2 (that is, the effective aperture of the reflective SLM 5) is c, the length of the line segment C-C1 is c1, and the line segment C Let the length of -C2 be c2. Further, a perpendicular foot from the point C to the line segment AB is a point D, a length of the perpendicular line CD is h, and a length of the line segment AB is L.

  Also in this embodiment, as in the first embodiment, the readout light (input light beam) is incident along the virtual reference straight line 9 from the input optical system (not shown) at a convergence angle in the range of 0 to α. Suppose you come. Further, it is assumed that the beam diameter when the reading light (input light beam) is incident on the reflection type SLM 5 is equal to the length c of the element reflection surface 5c. The readout light modulated by the reflection type SLM 5 and reflected by the element reflection surface 5 c is emitted from the reflection type SLM 5. Of the readout light, a desired component (that is, a desired component desired to be output from the spatial light modulator 30) is emitted as an output light beam with a divergence angle in the range of 0 to β. Also in the present embodiment, the input-side reflecting surface M1, the output-side reflecting surface M2, and the element reflecting surface 5c have the expressions (1) to (8) or the convergence angle value α and the desired divergence angle value β, or The relations of the expressions (11) to (16) are satisfied. For example, when the desired component is 1st to nth order diffracted light, the expressions (1) to (8) or the expressions (11) to (16) with respect to the convergence angle α and the desired diffraction order n. And the relations of the expressions (9) and (10) are satisfied.

  Therefore, also in the spatial light modulation device 30 of the present embodiment, the input principal ray 11 and the output principal ray 17 are both located on the virtual reference straight line 9 as in the spatial light modulation device 1 of the first embodiment. Therefore, when an optical system is created in combination with an input optical system or an output optical system, the entire optical system can be easily designed, assembled, and adjusted. Furthermore, if φ3 = 0, the design, assembly, and adjustment of the entire optical system are further facilitated. In addition, the entire optical system can be made compact. A plurality of spatial light modulators 30 can be connected in multiple stages along the virtual reference line 9. All of the incident light on the prism 32 is reflected by the input-side reflecting surface M1, and all of the incident light reflected by the input-side reflecting surface M1 enters the reflective SLM 5 as readout light, and is further modulated by the reflective SLM 5. However, all the desired components of the readout light are reflected by the output-side reflecting surface M2 of the prism 32. Therefore, it is possible to increase the light utilization efficiency and take advantage of the reflective SLM 5 having a high effective aperture ratio. In addition, according to the present embodiment, since the input side reflection surface M1 and the output side reflection surface M2 are provided in the single prism 32, the total number of parts is reduced, and the configuration is further simplified. Yes.

  Next, an optical processing device 60 that employs the spatial light modulation device 30 will be described with reference to FIG.

  The optical processing device 60 is a device for performing waveform shaping. The optical processing device 60 includes a laser 62, a lens 64, a pinhole 66, a collimating lens 68, a spatial light modulation device 30, a Fourier transform lens 70, and an output surface 72. The laser 62, the lens 64, the pinhole 66, and the collimating lens 68 constitute the input optical system I. The input optical system I also functions as a parallel light projecting optical system R. The Fourier transform lens 70 and the output surface 72 constitute an output optical system. The spatial light modulator 30 includes a prism 32 and a reflective SLM 5. The reflective SLM 5 is, for example, the PAL-SLM described with reference to FIG. 7, and is also incorporated in the phase modulation module 6 described with reference to FIG. However, in FIG. 16, only the reflection type SLM 5 is shown, and the phase modulation module 6 is not shown.

  The laser 62, the lens 64, the pinhole 66, the collimating lens 68, the Fourier transform lens 70, and the output surface 72 are disposed on the virtual reference line 9 together with the prism 32. The reflection type SLM 5 is arranged at a position shifted from the virtual reference straight line 9 in the vertical direction.

  The laser 62 emits linearly polarized light having a predetermined wavelength as readout light. The chief ray of the readout light propagates on the virtual reference line 9. The lens 64, the pinhole 66, and the collimating lens 68 convert the readout light into parallel light having a predetermined beam diameter. The parallel light propagates along the virtual reference line 9 and enters the input-side reflecting surface M1 of the prism 32. The input side reflection surface M1 reflects the incident parallel light toward the reflective SLM5. Reading light is incident on the reflective SLM 5 at a convergence angle α (= 0) and a beam diameter c. The reflective SLM 5 is built in the phase modulation module 6 (FIG. 7), and performs a desired phase modulation on the incident read light by a signal input to the LCD 530 (FIG. 7) from a control unit (not shown). The reflective SLM 5 reflects the phase-modulated light toward the prism 32. The principal ray of the phase-modulated light reflected by the output-side reflecting surface M2 propagates along the virtual reference straight line 9. The Fourier transform lens 70 performs a Fourier transform on the phase-modulated light, and forms a desired waveform pattern on the output surface 72.

  In the spatial light modulator 30, the prism 32 and the reflective SLM 5 have the expressions (1) to (8) or the expressions (11) to (16) and (for the convergence angle α and the desired maximum diffraction order n. It arrange | positions so that 9) and (10) may be satisfied. For this reason, all of the input light output from the input optical system I is incident on the input-side reflection surface M1 of the prism 32, and all of the light reflected by the input-side reflection surface M1 is incident on the reflection-type SLM5. All of the necessary components (1st to n-th order diffracted light) modulated in (4) are reflected by the output-side reflecting surface M2 of the prism 32 and Fourier transformed by the Fourier transform lens 70. Therefore, the light utilization efficiency can be increased, and the advantages of the reflective SLM 5 having a high effective aperture ratio can be utilized.

  In the optical processing device 60, as in the optical processing device 80 in the first embodiment described with reference to FIG. 13, the input optical system I and the output optical system O are arranged on the virtual reference straight line 9, Both the optical axis of the input light and the optical axis of the output light are located on the virtual reference line 9. The reflection type SLM 5 is at a position shifted from the virtual reference straight line 9 in the vertical direction. The laser 62, the lens 64, the pinhole 66, the collimating lens 68, the Fourier transform lens 70, and the output surface 72 are all arranged in such a direction that the virtual reference straight line 9 passes through the virtual reference straight line 9 orthogonally. Yes. Therefore, like the optical processing apparatus 80, the design, assembly, and adjustment of the optical system are easy, and the entire optical system can be made compact. In addition, since the spatial light modulation device 30 employs the prism 32, the total number of parts is reduced and the configuration is simplified.

  Next, another optical processing apparatus 100 employing the spatial light modulation device 30 will be described with reference to FIG.

  The optical processing device 100 is the optical processing according to the first embodiment described with reference to FIG. 13 except that the spatial light modulation device 30 is employed instead of the spatial light modulation device 1 according to the first embodiment. It is substantially the same as the device 80. That is, the light source 81, the pinhole 83, the collimating lens 82, the input surface 84, and the Fourier transform lens 86 constitute the input optical system I. Among these, the light source 81, the pinhole 83, and the collimating lens 82 constitute a parallel light projecting optical system R. The Fourier transform lens 88 and the output surface 90 constitute the output optical system O. The distance between the input surface 84 and the Fourier transform lens 86 and the distance through the prism 32 between the Fourier transform lens 86 and the element reflection surface 5c are the focal length (length f1) of the Fourier transform lens 86. Are set equal. The distance through the prism 32 between the element reflection surface 5c and the Fourier transform lens 88 and the distance between the Fourier transform lens 88 and the output surface 90 are the focal length (length f2) of the Fourier transform lens 88. Are set equal.

  The readout light (input light beam) is Fourier transformed by the Fourier transform lens 86, reflected by the prism 32, and incident on the reflective SLM 5 at a convergence angle α and a beam diameter c. The optical processing apparatus 100 having such a configuration performs a correlation operation between the input image displayed on the input surface 84 and the reference image displayed on the reflective SLM 5. The reflective SLM 5 is, for example, the PAL-SLM described with reference to FIG. 7, and is also incorporated in the phase modulation module 6 described with reference to FIG. However, in FIG. 17, only the reflection type SLM 5 is illustrated, and the phase modulation module 6 is not illustrated.

  In the spatial light modulator 30, the prism 32 and the reflective SLM 5 have the expressions (1) to (8) or the expressions (11) to (16) and (for the convergence angle α and the desired maximum diffraction order n. It arrange | positions so that 9) and (10) may be satisfied. Therefore, according to the optical processing apparatus 100, the same effect as that of the optical processing apparatus 80 can be obtained. Moreover, since the spatial light modulation device 30 employs the prism 32, the total number of parts is further reduced and the configuration is simpler. It has become.

  Next, an optical processing apparatus 200 in which two spatial light modulators 30 are connected in two stages in a cascade manner along the virtual reference straight line 9 will be described with reference to FIG.

  Similar to the optical processing device 100 described with reference to FIG. 17, the optical processing device 200 includes a spatial light modulation device 30 (hereinafter, a second spatial light modulation device 30) between the Fourier transform lens 86 and the Fourier transform lens 88. -2). The optical processing device 200 further includes another spatial light modulation device 30 (hereinafter referred to as a first spatial light modulation device 30-1) between the collimating lens 82 and the Fourier transform lens 86 instead of the input surface 84. ). Both the first spatial light modulator 30-1 and the second spatial light modulator 30-2 have the same configuration as the spatial light modulator 30 described with reference to FIG. That is, the first spatial light modulation device 30-1 includes a reflective SLM 5 (hereinafter referred to as a first reflective SLM 5-1) and a prism 32 (hereinafter referred to as a first prism 32-1). . The reflective SLM 5-1 is shifted from the virtual reference line 9 in a direction perpendicular to the virtual reference line 9. The input-side reflecting surface M1 and the output-side reflecting surface M2 of the prism 32-1 are arranged on the virtual reference straight line 9. The second spatial light modulator 30-2 includes a reflective SLM 5 (hereinafter referred to as a second reflective SLM 5-2) and a prism 32 (hereinafter referred to as a second prism 32-2). The reflective SLM 5-2 is shifted from the virtual reference line 9 in a direction perpendicular to the virtual reference line 9, and the input-side reflection surface M1 and the output-side reflection surface M2 of the prism 32-2 are on the virtual reference line 9. Has been placed.

The light source 81, the pinhole 83, the collimating lens 82, and the element reflection surface 5c of the reflective SLM 5-1 of the first spatial light modulator 30-1 constitute the input optical system I. Among these, the light source 81, the pinhole 83, and the collimating lens 82 constitute a parallel light projecting optical system R. The Fourier transform lens 88 and the output surface 90 constitute an output optical system O. The distance through the prism 32-1 between the element reflection surface 5c of the reflection type SLM5-1 and the Fourier transform lens 86, and the prism 32 between the Fourier transform lens 86 and the element reflection surface 5c of the reflection type SLM5-2. The distance through -2 is set equal to the focal length (length f1) of the Fourier transform lens 86. The distance through the prism 32-2 between the element reflection surface 5c of the reflective SLM5-2 and the Fourier transform lens 88 and the distance between the Fourier transform lens 88 and the output surface 90 are the same as those of the Fourier transform lens 88. It is set equal to the focal length (length f2). Both the reflection type SLMs 5-1 and 5-2 are, for example, the PAL-SLMs described with reference to FIG. 7, and are each incorporated in the phase modulation module 6 described with reference to FIG. In FIG. 18, only the reflection type SLMs 5-1 and 5-2 are illustrated and the phase modulation module 6 is not illustrated for the sake of clarity. Reflective SLM5-1 displays the patterns created from the input image, and outputs the input image by phase modulating the collimated light from the collimating lens 82. The reflective SLM 5-2 displays a filter pattern created based on the reference image. Similar to the optical processing apparatus 100, the optical processing apparatus 200 having such a configuration performs a correlation operation between the input image and the reference image.

  The readout light is collimated by the collimating lens 82, reflected by the prism 32-1, and enters the reflective SLM 5-1 with a beam diameter c and a convergence angle α (= 0). The prism 32-1 and the reflective SLM 5-1 have the following expressions (1) to (8) or (11) to (16) for the convergence angle α (= 0) and the desired maximum diffraction order n. They are arranged so as to satisfy (9) and (10).

  The 1st to nth order diffracted light emitted from the reflective SLM 5-1 is Fourier transformed by the Fourier transform lens 86, reflected by the prism 32-2, and reflected to the reflective SLM 5-2 with a beam diameter c and a convergence angle α. Incident. The prism 32-2 and the reflection type SLM 5-2 have the expressions (1) to (8) or the expressions (11) to (16) and (9) with respect to the convergence angle α and the desired maximum diffraction order n. It arrange | positions so that (10) may be satisfied.

  Therefore, in addition to achieving the same effect as the optical processing device 100, the optical processing device 200 can easily generate an arbitrary input image by the first spatial light modulation device 30-1. Even if the two spatial light modulators 30 are connected in multiple stages, the optical axes related to the collimating lens 82, the Fourier transform lens 86, and the Fourier transform lens 88 all extend on a single virtual reference line 9, and thus optical. System design, assembly and adjustment are easy.

  Next, another optical processing device 300 employing the spatial light modulation device 30 will be described with reference to FIG.

  The optical processing device 300 is an example of a wavefront compensation optical system that forms a wavefront having a uniform wavefront or a desired phase distribution by compensating for distortion of an input wavefront. The optical processing device 300 is used in combination with a beam control optical system used in an optical measurement optical system, a laser processing optical system, an optical manipulation, and the like, and removes these aberrations.

  The optical processing device 300 includes a light source 81, a pinhole 83, a collimating lens 82, an input surface 302, a relay lens system including a lens 304 and a lens 306, and a spatial light modulation device 30, a relay lens system including a lens 308 and a lens 310. , A beam sampler 312, a wavefront sensor 314, a control device 316, and an output surface 318. The spatial light modulation device 30 includes a reflective SLM 5 and a prism 32. In this example, the reflective SLM 5 is the PAL-SLM described with reference to FIG. 7 and is also incorporated in the phase modulation module 6 described with reference to FIG. In FIG. 19, only the reflective SLM 5 is shown in the components inside the phase modulation module 6 and other components are not shown for the sake of clarity.

  The light source 81, the pinhole 83, the collimating lens 82, the input surface 302, the lens 304, and the lens 306 constitute an input optical system I. Among these, the light source 81, the pinhole 83, and the collimating lens 82 constitute a parallel light projecting optical system R. The lens 308, the lens 310, the beam sampler 312, and the output surface 318 constitute an output optical system O. The light source 81, the pinhole 83, the collimating lens 82, the input surface 302, the lens 304, the lens 306, the prism 32, the lenses 308 and 310, the beam sampler 312, and the output surface 318 are arranged on the virtual reference line 9. . The beam sampler 312 is a half mirror disposed at an angle of 45 degrees with respect to the virtual reference line 9. The reflective SLM 5 and the control device 316 are provided at positions shifted from the virtual reference line 9 in a direction perpendicular to the virtual reference line 9. The input surface 302, the output surface 318, the reflective SLM 5, and the wavefront sensor 314 are maintained in an imaging relationship by lenses 304, 306, 308, and 310. In this example, the relay lens system including the lens 304 and the lens 306 and the relay lens system including the lens 308 and the lens 310 transmit the image as it is.

  The light source 81 is a laser and emits linearly polarized light (reading light) having a predetermined wavelength, and the pinhole 83 and the collimating lens 82 convert the reading light into substantially parallel light having a predetermined beam diameter. The substantially parallel light is incident on the input surface 302 via an optical medium (not shown) such as a measurement target object or the atmosphere that causes the wavefront to be distorted. The light beam incident on the input surface 302 has distortion due to the optical medium. The light beam passes through the lens 304 and the lens 306, is reflected by the prism 32, and forms an image on the reflective SLM 5. The light that is phase-modulated and reflected by the reflective SLM 5 is reflected by the prism 32, passes through the lens 308 and the lens 310, and forms an image on the output surface 318. Here, a part of the light transmitted through the lens 310 is sampled by the beam sampler 312 disposed behind the lens 310 and enters the wavefront sensor 314. The wavefront sensor 314 measures the distortion of the incident beam wavefront, feeds back a signal for correcting the distortion to the LCD 530 (FIG. 7) in the phase modulation module 6 via the control device 316, and performs wavefront compensation. A condensing optical system (not shown) is disposed after the output surface 318, and irradiates light to a sensor, a processing object, a manipulation object, or the like.

  In the spatial light modulator 30, the prism 32 and the reflective SLM 5 are arranged so as to satisfy the expressions (1) to (8) or the expressions (11) to (16) and the expressions (9) and (10). Has been. Here, in these equations, α is set to a value larger than the maximum distortion amount that can be compensated by the reflective SLM 5. Β is set to a value larger than the allowable residual.

  Therefore, all the components that can be compensated by the SLM 5 in the input light output from the input optical system I are incident on the input-side reflecting surface M1 of the prism 32, and all the light reflected by the input-side reflecting surface M1 is reflected-type SLM 5. Then, all of the allowable components of the light modulated by the reflective SLM 5 and modulated by the reflective SLM 5 are reflected by the output-side reflective surface M 2 of the prism 32 and guided to the output optical system O. Therefore, the light utilization efficiency can be increased, and the advantages of the reflective SLM 5 having a high effective aperture ratio can be utilized.

  Further, since the optical path can be bent vertically by the beam sampler 312, the design of the optical system is simplified. Furthermore, since the optical path is not diagonal but extends in a direction parallel or perpendicular to the virtual reference straight line 9, consistency with the casing of the phase modulation module 6 and the wavefront sensor 314, which are generally rectangular parallelepipeds, is secured. It is easy to make the entire optical processing apparatus 300 compact. In addition, since the prism 32 is used, the total number of parts is reduced and the configuration can be made more compact.

  An optical path from the input surface 302 to the output surface 318 is arranged on the virtual reference straight line 9, and the spatial light modulator 30 is inserted on this optical path. For this reason, optical adjustment becomes easy as in the optical processing apparatuses 60, 100, and 200 described above. When performing the optical adjustment, the optical components other than the spatial light modulator 30 may be optically adjusted, and then the spatial light modulator 30 may be inserted and adjusted.

  Note that the optical processing device 300 does not have to have the configuration described with reference to FIG. 19 as long as it includes the spatial light modulation device 30 and realizes wavefront compensation. For example, the light source 81 may be a laser, but may not be a laser as long as the spatial coherence is high and can be regarded as a point light source. Further, the beam sampler 312 may not be disposed behind the lens 310. The beam sampler 312 can be disposed at an arbitrary position on the rear side of the output side reflection surface M2 and on the front side of the output surface 318. Further, instead of the relay lens system comprising the lens 308 and the lens 310 between the reflective SLM 5 and the wavefront sensor 314, an enlargement relay lens system having an image enlargement function, or a reduction relay lens having an image reduction function A functional optical system having an arbitrary function, such as a dichroic mirror having a function of separating light for each system and wavelength, may be inserted. Further, the reflection type SLM 5 and the wavefront sensor 314 may not be in an imaging relationship.

  Next, a spatial light modulation device 40 according to the third embodiment will be described with reference to FIG.

  The spatial light modulation device 40 is the same as the spatial light modulation device 30 according to the second embodiment except that a prism 42 is employed instead of the prism 32. Therefore, the spatial light modulation device 40 includes a reflective SLM 5 and a prism 42. In FIG. 20, members having the same functions and configurations as those of the spatial light modulation device 30 according to the second embodiment are denoted by the same reference numerals. For the sake of clarity, only the mirror layer 5b of the reflective SLM 5 is shown, and the modulation unit 5a and the address unit 5d are not shown. The reflective SLM 5 is, for example, the PAL-SLM described with reference to FIG. 7, and may be incorporated in the phase modulation module 6 (FIG. 7).

  The prism 42 is a quadrangular prism having a trapezoidal cross section. More specifically, the prism 42 has a trapezoidal cross section formed by cutting off the apex portion of the triangular cross section of the prism 32. Of the four surfaces S1, S2, S3, and S4 (outer surface) constituting the quadrangular prism, two slopes S1 and S2 corresponding to the hypotenuse of the trapezoidal cross section are subjected to processing for increasing the reflectance. For this reason, S1 and S2 function as the input side reflection surface M1 and the output side reflection surface M2. In the prism 42, the input-side reflecting surface M1 and the output-side reflecting surface M2 are located on the virtual reference straight line 9, and the remaining two surfaces (bottom surface S3, upper surface S4) corresponding to the lower and upper bases of the trapezoidal cross section are formed. It arrange | positions so that the virtual reference straight line 9 may be pinched | interposed.

  The input-side reflection surface M1 reflects input light incident along the virtual reference straight line 9 to the reflective SLM 5. The reflective SLM 5 modulates and reflects the input light reflected by the input side reflection surface M1. The output-side reflection surface M2 reflects the light from the reflective SLM 5 and outputs it along the virtual reference line 9.

  Also in the present embodiment, as in the second embodiment, the readout light (input light beam) is incident at a convergence angle in the range of 0 to α along the virtual reference straight line 9 from an input optical system (not shown). Suppose you come. Further, it is assumed that the beam diameter when the reading light (input light beam) is incident on the reflection type SLM 5 is equal to the length c of the element reflection surface 5c. The readout light modulated by the reflection type SLM 5 and reflected by the element reflection surface 5 c is emitted from the reflection type SLM 5. Of this readout light, a desired component (that is, a desired component desired to be output from the spatial light modulator 40) is emitted as an output light beam with a divergence angle in the range of 0 to β. Here, the arrangement relationship among the input side reflection surface M1, the output side reflection surface M2, and the element reflection surface 5c is that the end point A2 of the input side reflection surface M1 and the end point B1 of the output side reflection surface M2 are separated from each other. Except for this, it is the same as the prism 32 of the second embodiment. In other words, the input-side reflection surface M1, the output-side reflection surface M2, and the element reflection surface 5c have the expressions (1) to (8) or the expressions (11) to (11) with respect to the convergence angle value α and the desired value β. The relationship of (16) is satisfied. For example, when it is desired to output 1st to nth order diffracted light, the expressions (1) to (8), or the expressions (11) to (16), and the convergence angle value α and the desired diffraction order n, and , Expressions (9) and (10) are satisfied.

  Therefore, the spatial light modulation device 40 of the present embodiment has the same effects as the spatial light modulation device 30 of the second embodiment and the spatial light modulation device 1 of the first embodiment. Therefore, the spatial light modulator 40 may be provided in place of the spatial light modulator 30 in the optical processing devices 60, 100, 200, and 300 described with reference to FIGS. In the optical processing device 80 described with reference to FIG. 13, the spatial light modulation device 40 may be provided instead of the spatial light modulation device 1.

  When the input-side reflecting surface M1, the output-side reflecting surface M2, and the element reflecting surface 5c satisfy the relationships of the expressions (11) to (16), the element reflecting surface 5c and the surface S3 of the prism 42, S4 is arranged in parallel to the virtual reference line 9. In this case, the spatial light modulation device 40 can perform vertical reading in addition to the oblique reading via the input-side reflection surface M1 and the output-side reflection surface M2. That is, as indicated by the arrow V, light is incident perpendicularly to the bottom surface S3 of the prism 42. Then, the light passes through the prism 42, exits vertically from the upper surface S 4, and enters the reflective SLM 5 perpendicularly. The light modulated and reflected by the reflection type SLM 5 is incident on the upper surface S4 of the prism 42 perpendicularly, passes through the prism 42 again, and exits from the bottom surface S3 vertically. At this time, since the incident light and the outgoing light travel perpendicularly to the bottom surface S3 and the top surface S4 of the prism 42, they are efficiently transmitted through the prism 42 without being reflected by the bottom surface S3 and the top surface S4.

  Next, a spatial light modulation device 50 according to a fourth embodiment and a coupling prism 52 used in the spatial light modulation device 50 will be described with reference to FIG.

  The spatial light modulator 50 is the second embodiment described with reference to FIG. 15 except that a coupling prism 52 is used instead of the prism 32 and the coupling prism 52 is joined to the reflective SLM 5. This is the same as the spatial light modulation device 30 according to the embodiment. Accordingly, the spatial light modulation device 50 includes a reflective SLM 5 and a coupling prism 52 joined to the reflective SLM 5. In FIG. 21, members having the same functions and configurations as those of the spatial light modulation device 30 according to the second embodiment are denoted by the same reference numerals. The reflective SLM 5 is, for example, the PAL-SLM described with reference to FIG. 7, and may be incorporated in the phase modulation module 6 (FIG. 7).

  The coupling prism 52 is a pentagonal prism. The coupling prism 52 has five surfaces 54, 55, 56, 57 and 58. The surface 54 faces the surface 58. The surface 54 and the surface 58 extend parallel to each other. The surface 56 faces the surface 55 and the surface 57. The angle (inner angle) formed by the surface 54 and the surface 56 is 90 °. The angle (inner angle) formed by the surface 56 and the surface 58 is also 90 °. The angle (inner angle) formed by the surface 54 and the surface 55 is 90 ° −φ1. The angle (inner angle) formed by the surface 57 and the surface 58 is 90 ° −φ2. The angle (inner angle) formed by the surface 55 and the surface 57 is 180 ° + (φ1 + φ2). Here, φ1 and φ2 are 0 ° <(90 ° −φ1) <90 °, 0 ° <(90 ° −φ2) <90 °, and 180 ° <{180 ° + (φ1 + φ2)} <360 °. Is satisfied. The surface 56 is bonded to the outer surface of the modulation unit 5a of the reflective SLM 5. For example, when the reflective SLM 5 is the PAL-SLM described with reference to FIG. 7, the surface 56 is bonded to the transparent substrate 502 of the reflective SLM 5. The element reflection surface 5 c extends parallel to the surface 56.

  The coupling prism 52 is arranged in the direction shown in FIG. 21 with respect to the virtual reference straight line 9. That is, the virtual reference straight line 9 passes through the surface 54 and the surface 58. The surface 54 and the surface 58 extend perpendicular to the virtual reference straight line 9. The surface 56 extends parallel to the virtual reference line 9 at a position shifted from the virtual reference line 9 in a direction perpendicular to the virtual reference line 9. Therefore, the element reflection surface 5 c also extends parallel to the virtual reference line 9 at a position shifted from the virtual reference line 9 in a direction perpendicular to the virtual reference line 9. The surface 55 extends obliquely with respect to the virtual reference straight line 9. The surface 57 also extends obliquely with respect to the virtual reference straight line 9. That is, the surface 55 extends in a direction that forms an angle φ1 with respect to the virtual reference straight line 9. The surface 57 extends in a direction that forms an angle φ2 with respect to the virtual reference straight line 9. Note that φ1 takes a positive value counterclockwise from the virtual reference line 9 in FIG. Further, φ2 takes a positive value in the clockwise direction from the virtual reference straight line 9 in FIG. φ1 and φ2 satisfy 0 ° <φ1 <90 ° and 0 ° <φ2 <90 °. In the present embodiment, the angle φ1 and the angle φ2 are values satisfying the condition of total reflection with respect to the refractive index m of the material constituting the coupling prism 52.

  The surface 54 functions as the input side transmission surface P1, the surface 56 functions as the bonding transmission surface P2, and the surface 58 functions as the output side transmission surface P3. The inner surface of the surface 55 functions as the input side reflecting surface M1, and the inner surface of the surface 57 functions as the output side reflecting surface M2.

  That is, the readout light propagating along the virtual reference straight line 9 passes through the input side transmission surface P <b> 1 and is guided into the coupling prism 52. The readout light propagates through the coupling prism 52 and is totally reflected by the input-side reflection surface M1, further propagates through the coupling prism 52, passes through the cemented transmission surface P2, and reaches the reflection type SLM5. The readout light modulated by the modulation unit 5 a and reflected by the element reflection surface 5 c is transmitted again through the bonding transmission surface P <b> 2 and guided into the coupling prism 52. The readout light propagates through the coupling prism 52 and is totally reflected by the output-side reflecting surface M2, further propagates through the coupling prism 52, passes through the output-side transmitting surface P3, and is output from the coupling prism 52. And propagates along the virtual reference line 9.

  Also in the present embodiment, the end point A2 of the input side reflection surface M1 and the end point B1 of the output side reflection surface M2 coincide with each other as in the prism 32 of the second embodiment described with reference to FIG. In other words, the arrangement relationship among the input side reflection surface M1, the output side reflection surface M2, and the element reflection surface 5c is that the end point A2 of the input side reflection surface M1 and the end point B1 of the output side reflection surface M2 are coincident. The arrangement relationship between the input side reflection surface M1, the output side reflection surface M2, and the element reflection surface 5c in the first embodiment described with reference to FIG. 8 is the same.

  That is, as shown in FIG. 21, the point where the input chief ray 11 is incident on the input side reflecting surface M1 is a point A, and the point where the chief ray of the light reflected by the input side reflecting surface M1 is incident on the reflective SLM 5 is a point C. A point B is a point where a principal ray of light modulated by the reflective SLM 5 and reflected by the element reflection surface 5c is incident on the output-side reflection surface M2. A straight line AB connecting the point A and the point B is located on the virtual reference straight line 9. The angle formed between the input side reflection surface M1 and the virtual reference line 9 is φ1 (0 <φ1 <90 °), and the angle formed between the output side reflection surface M2 and the virtual reference line 9 is φ2 (0 <φ2 <90 °). is there. The element reflecting surface 5c extends in a direction that forms an angle φ3 with respect to the virtual reference straight line 9. Note that φ3 takes a positive value counterclockwise from the virtual reference line 9 in FIG. In this example, φ3 satisfies φ3 = 0. In addition, with respect to the points A1 and A2 at both ends of the input side reflection surface M1, the length of the line segment A1-A2 is a, the length of the line segment A-A1 is a1, and the length of the line segment A-A2 is Let a2. The length of the line segment B1-B2 is b, the length of the line segment B-B1 is b1, and the length of the line segment B-B2 is b2 with respect to the points B1 and B2 at both ends of the output-side reflecting surface M2. To do. For the two end points C1 and C2 of the element reflecting surface 5c, the length of the line segment C1-C2 (that is, the effective aperture of the reflective SLM 5) is c, the length of the line segment C-C1 is c1, and the line segment C Let the length of -C2 be c2. Further, a perpendicular foot from the point C to the line segment AB is a point D, a length of the perpendicular line CD is h, and a length of the line segment AB is L.

  Also in the present embodiment, as in the second and third embodiments, the readout light (input light beam) is converged at a convergence angle in the range of 0 to α along the virtual reference line 9 from an input optical system (not shown). And enter. Further, it is assumed that the beam diameter when the reading light (input light beam) is incident on the reflection type SLM 5 is equal to the length c of the element reflection surface 5c. Further, the readout light modulated by the reflective SLM 5 and reflected by the element reflective surface 5 c is emitted from the reflective SLM 5. It is assumed that a desired component (that is, a desired component desired to be output from the spatial light modulator 50) of the readout light is emitted as an output light beam with a divergence angle in the range of 0 degrees to an angle β.

を満足している。
例えば、所望の成分が１〜ｎ次回折光である場合には、入力側反射面Ｍ１、出力側反射面Ｍ２、素子反射面５ｃは収束角度値αと所望の回折次数ｎとに対して、式（１１´）〜（１６´）、及び、式（９´）、（１０´）とを満足している。ここで式（９´）、（１０´）は、

となる。In the present embodiment, the input-side reflecting surface M1, the output-side reflecting surface M2, and the element reflecting surface 5c are expressed by equations (11) to (16) with respect to the convergence angle value α and the desired divergence angle value β. Satisfying equations (11 ′) to (16 ′) where α is replaced with α / m, β is replaced with β / m, and λ is replaced with λ / m (where m is the refractive index of the coupling prism 52) is doing.
That is,

Is satisfied.
For example, when the desired component is 1 to n-th order diffracted light, the input-side reflecting surface M1, the output-side reflecting surface M2, and the element reflecting surface 5c are expressed with respect to the convergence angle value α and the desired diffraction order n. (11 ′) to (16 ′) and the expressions (9 ′) and (10 ′) are satisfied. Here, the equations (9 ′) and (10 ′) are

It becomes.

  Therefore, also in the spatial light modulation device 50 of the present embodiment, both the input principal ray 11 and the output principal ray 17 are located on the virtual reference straight line 9, and all of the incident light to the prism 52 is caused by the input side reflection surface M1. All of the incident light reflected and reflected by the input-side reflecting surface M1 enters the reflective SLM 5 as readout light, and all the desired components of the readout light modulated by the reflective SLM 5 are output on the prism 52 side. Reflected by the reflecting surface M2. Therefore, according to the spatial light modulation device 50, the same effect as the spatial light modulation device 30 of the second embodiment and the spatial light modulation device 1 of the first embodiment can be obtained. Therefore, the spatial light modulator 50 may be provided in place of the spatial light modulator 30 in the optical processing apparatuses 60, 100, 200, and 300 described with reference to FIGS. Further, in the optical processing device 80 described with reference to FIG. 13, the spatial light modulation device 50 may be provided instead of the spatial light modulation device 1.

  Furthermore, since the input-side reflecting surface M1 and the output-side reflecting surface M2 are provided at a predetermined angle for total reflection, the input-side reflecting surface M1 and the output-side reflecting surface M2 have a process for improving the reflectance. There is no need to apply. Since the input-side transmission surface P1 and the output-side transmission surface P3 are orthogonal to the virtual reference line 9, no stray light is generated in the coupling prism 52.

  Further, according to the spatial light modulation device 50, when the optical path length is adjusted, the coupling prism 52 and the reflective SLM 5 may be moved integrally in a direction perpendicular to the virtual reference straight line 9. Adjustment is extremely easy. At this time, the input-side transmission surface P1, the input-side reflection surface M1, the output-side reflection surface M2, and the output-side transmission surface P3 may be made large in advance so that all necessary components are transmitted or reflected after movement.

  Note that the angle φ1 formed between the input-side reflection surface M1 and the virtual reference line 9 and the angle φ2 formed between the output-side reflection surface M2 and the virtual reference line 9 do not have to satisfy the condition for total reflection. good. In that case, the input-side reflecting surface M1 (the inner surface of the surface 55) and the output-side reflecting surface M2 (the inner surface of the surface 57) may be subjected to a process for increasing the reflectance.

を満足していればよい。In the above description, the surface 56 and the element reflection surface 5 c extend in parallel to the virtual reference straight line 9. That is, φ3 = 0. However, the surface 56 and the element reflection surface 5 c may extend obliquely with respect to the virtual reference straight line 9. That is, φ3 may not be zero (0). In this case, the input-side reflecting surface M1, the output-side reflecting surface M2, and the element reflecting surface 5c are set to α / α in the equations (1) to (8) with respect to the convergence angle value α and the desired value β. It suffices to satisfy the equation in which β is replaced by m, β is replaced by β / m, and λ is replaced by λ / m.
That is, it is sufficient if the following expressions (1 ′) to (8 ′) are satisfied.

As long as you are satisfied.

  For example, when the desired component is 1st to nth order diffracted light, the input-side reflecting surface M1, the output-side reflecting surface M2, and the element reflecting surface 5c have a convergence angle value α and a desired diffraction order n. It is sufficient that the expressions (1 ′) to (8 ′) and the expressions (9 ′) and (10 ′) are satisfied.

  The preferred embodiments of the spatial light modulation device, the optical processing device, the coupling prism, and the method of using the coupling prism according to the present invention have been described above with reference to the accompanying drawings. It is not limited to. Those skilled in the art can make various modifications and improvements within the scope of the technical idea described in the claims.

  For example, any of the spatial light modulators 1, 30, 40, and 50 can be applied to the optical processing apparatuses 60, 80, 100, 200, and 300. If each of the spatial light modulators 1, 30, 40, 50 is combined with an arbitrary input optical system and an arbitrary output optical system, an arbitrary process can be performed on an arbitrary light including arbitrary information.

  The reflective SLM 5 of the above embodiment may not be a PAL-SLM. The reflective SLM 5 can be composed of any reflective spatial light modulator. Specifically, the reflective SLM 5 may be a liquid crystal type or a non-liquid crystal type. The reflective SLM 5 may be an optical address type or an electrical address type. The reflective SLM 5 may be a phase modulation type that modulates the phase of the readout light, an intensity modulation type that modulates the intensity of the readout light, or a complex amplitude modulation type that modulates both the phase and intensity of the readout light. May be.

  For example, when the reflective SLM 5 is an LCoS (Liquid Crystal on Silicon) type, there is a non-operation area (gap) between the pixels. For this reason, unnecessary diffracted light derived from this structure is generated. In such a case, instead of setting a value satisfying Equation (10) as a value of δ satisfying Equation (9), a value of the maximum divergence angle of unnecessary diffracted light may be set. For δ and α, the parameters φ1, φ2, c, c1, h, a1, a2, b1, b2, and L are expressed by equations (1) to (8) or equations (11) to (16) and equations. (9) (or Expressions (1 ′) to (8 ′) or Expressions (11 ′) to (16 ′) and Expression (9 ′)) are satisfied, and Expressions (4) to (7) Alternatively, the input light is effective if selected so that the equal sign is established in the mathematical expressions (14) to (16) (or the mathematical expressions (4 ′) to (7 ′) or the mathematical expressions (14 ′) to (16 ′)). The unnecessary light is not output from the spatial light modulators 1, 30, 40 and 50 while the required diffracted light is effectively output from the spatial light modulators 1, 30, 40 and 50 by irradiating the reflective SLM 5 with the light. Can be.

  For example, when the reflective SLM 5 is composed of a reflective spatial light modulator using a nonlinear optical crystal, the modulation unit 5a includes a nonlinear optical crystal.

  When the reflective SLM 5 is formed of a variable mirror, the mirror layer 5b modulates the read light while reflecting the read light by changing the shape of the element reflection surface 5c. Thus, in the variable mirror, the mirror layer 5b itself also serves as the modulation unit 5a. For this reason, when the reflective SLM 5 is composed of a variable mirror, as shown in FIG. 22, the element reflective surface 5c of the reflective SLM 5 is exposed to the outside and faces the input-side reflective surface M1 and the output-side reflective surface M2. .

The spatial light modulator according to the present invention, the optical processing equipment,及 Beauty, the use of the coupling prism, the wavefront compensation system, patterning systems, holographic systems, 3D display displaying system, an optical information processing system or the like, various optical processing Widely available for the system.

Claims (4)

A reflective spatial light modulator provided at a position shifted from a virtual reference line in a direction perpendicular to the virtual reference line;
An input-side reflecting surface that is provided on the virtual reference straight line and reflects the incident light incident along the virtual reference straight line so as to be incident obliquely as read light on the reflective spatial light modulator;
An output-side reflecting surface provided on the virtual reference straight line, for reflecting the read light modulated by the reflective spatial light modulator and reflected obliquely and outputting the reflected light as outgoing light along the virtual reference straight line; ,
With
The reflective spatial light modulator comprises an element reflecting surface for reflecting the reading light from the input-side reflecting surface;
The input-side reflecting surface and the output-side reflecting surface are separated by a distance L along the virtual reference line, and the element reflecting surface is a distance h in a direction perpendicular to the virtual reference line from the virtual reference line. The input-side reflection surface, the output-side reflection surface, and the element reflection surface are inclined by angles φ1, φ2, and φ3, respectively, with respect to the direction in which the virtual reference straight line extends,
The element reflecting surface has a size c;
The input-side reflecting surface has a size a1 on the side far from the reflective spatial light modulator with respect to the virtual reference line, and a size a2 on the side close to the reflective spatial light modulator;
The output-side reflective surface has a size b1 closer to the virtual reference straight line from the reflective spatial light modulator and a size b2 farther from the reflective spatial light modulator;
The element reflection surface has a size c1 closer to the input reflection surface with respect to the optical axis of the incident light reflected by the input reflection surface;
The reflective spatial light modulation element modulates the reading light incident at a convergence angle in the range of 0 to α, and emits the predetermined component at a divergence angle in the range of 0 to β.
When the readout light incident on the reflective spatial light modulator is convergent light, α takes a positive value, and when divergent light, α takes a negative value and is emitted from the reflective spatial light modulator. When the predetermined component of the readout light is divergent light, β takes a positive value, and when it is convergent light, β takes a negative value,
The distances L and h and the angles φ1, φ2, and φ3 satisfy the following expressions (1) and (2):
The sizes c, c1, a1, a2, b1, and b2 satisfy the following expressions (3) to (8) with respect to α and β,
The predetermined component is a diffraction component having a diffraction order of 1 or more and n (n is a natural number greater than 0), and α and β are displayed on the wavelength λ of the incident light and the reflective spatial light modulator. A spatial light modulator characterized by satisfying the following equations (9) and (10) for the lattice constant d of the smallest possible lattice pattern .

A reflective spatial light modulator provided at a position shifted from a virtual reference line in a direction perpendicular to the virtual reference line;
An input-side reflecting surface that is provided on the virtual reference straight line and reflects the incident light incident along the virtual reference straight line so as to be incident obliquely as read light on the reflective spatial light modulator;
An output-side reflecting surface provided on the virtual reference straight line, for reflecting the read light modulated by the reflective spatial light modulator and reflected obliquely and outputting the reflected light as outgoing light along the virtual reference straight line; ,
With
The reflective spatial light modulator comprises an element reflecting surface for reflecting the reading light from the input-side reflecting surface;
The input-side reflecting surface and the output-side reflecting surface are separated by a distance L along the virtual reference line, and the element reflecting surface is a distance h in a direction perpendicular to the virtual reference line from the virtual reference line. The input-side reflection surface, the output-side reflection surface, and the element reflection surface are inclined by angles φ1, φ2, and φ3, respectively, with respect to the direction in which the virtual reference straight line extends,
A single coupling prism includes an input-side transmission surface, a first reflection surface, a bonded transmission surface, a second reflection surface, and an output-side transmission surface,
The input-side transmission surface is provided on the virtual reference line, transmits incident light incident along the virtual reference line, and guides the incident light along the virtual reference line.
The first reflection surface is an input-side reflection surface that is provided on the virtual reference line and reflects incident light propagating from the input-side transmission surface along the virtual reference line.
The bonded transmission surface is provided at a position shifted from the virtual reference line in a direction perpendicular to the virtual reference line, bonded to the reflective spatial light modulator, reflected by the first reflection surface, and internally The incident light propagating through the light is transmitted and incident obliquely on the reflective spatial light modulator as read light, and the read light modulated and reflected obliquely by the reflective spatial light modulator To propagate through the inside,
The second reflecting surface is provided on the virtual reference straight line, and reflects the reading light propagating through the junction transmission surface to propagate the inside as the outgoing light along the virtual reference straight line. Side reflecting surface,
The output-side transmission surface is provided on the virtual reference line, and outputs outgoing light propagating from the second reflection surface along the virtual reference line to the outside along the virtual reference line. ,
The refractive index of the coupling prism is m,
The element reflecting surface has a size c;
The input-side reflecting surface has a size a1 on the side far from the reflective spatial light modulator with respect to the virtual reference line, and a size a2 on the side close to the reflective spatial light modulator;
The output-side reflective surface has a size b1 closer to the virtual reference straight line from the reflective spatial light modulator and a size b2 farther from the reflective spatial light modulator;
The element reflection surface has a size c1 closer to the input reflection surface with respect to the optical axis of the incident light reflected by the input reflection surface;
The reflective spatial light modulation element modulates the reading light incident at a convergence angle in the range of 0 to α, and emits the predetermined component at a divergence angle in the range of 0 to β.
When the readout light incident on the reflective spatial light modulator is convergent light, α takes a positive value, and when divergent light, α takes a negative value and is emitted from the reflective spatial light modulator. When the predetermined component of the readout light is divergent light, β takes a positive value, and when it is convergent light, β takes a negative value,
The distances L and h and the angles φ1, φ2, and φ3 satisfy the following expressions (1) and (2):
The sizes c, c1, a1, a2, b1, b2 satisfy the following expressions (3 ′) to (8 ′) with respect to α and β:
The predetermined component is a diffraction component having a diffraction order of 1 or more and n (n is a natural number greater than 0), and α and β are displayed on the wavelength λ of the incident light and the reflective spatial light modulator. A spatial light modulation device satisfying the following expressions (9 ′) and (10 ′) with respect to the lattice constant d of the smallest possible lattice pattern .

A spatial light modulator;
An input optical system that is provided on the virtual reference straight line and inputs incident light to the spatial light modulator along the virtual reference straight line;
An output optical system provided on the virtual reference straight line, for processing the emitted light output from the spatial light modulator along the virtual reference straight line;
The spatial light modulator is
A reflective spatial light modulator provided at a position shifted from the virtual reference line in a direction perpendicular to the virtual reference line;
An input provided on the virtual reference straight line for reflecting incident light incident from the input optical system along the virtual reference straight line and making it incident obliquely as read light on the reflective spatial light modulator A side reflecting surface;
An output-side reflecting surface provided on the virtual reference straight line, for reflecting the read light modulated by the reflective spatial light modulator and reflected obliquely and outputting the reflected light as outgoing light along the virtual reference straight line; ,
With
The reflective spatial light modulator comprises an element reflecting surface for reflecting the reading light from the input-side reflecting surface;
The input-side reflecting surface and the output-side reflecting surface are separated by a distance L along the virtual reference line, and the element reflecting surface is a distance h in a direction perpendicular to the virtual reference line from the virtual reference line. The input-side reflection surface, the output-side reflection surface, and the element reflection surface are inclined by angles φ1, φ2, and φ3, respectively, with respect to the direction in which the virtual reference straight line extends,
The distances L and h and the angles φ1, φ2, and φ3 satisfy the following expressions (1) and (2):
The input optical system has a first lens for Fourier transforming an input image,
The reflective spatial light modulator phase-modulates a Fourier transform image of the input image with a filter pattern based on a reference image,
The output optical system has a second lens that Fourier transforms the output light from the spatial light modulator, and outputs an image indicating a correlation between the input image and the reference image,
An input image creating means for creating the input image;
The input image creating means is composed of another spatial light modulator,
The another spatial light modulator is:
A reflective spatial light modulator provided at a position shifted from the virtual reference line in a direction perpendicular to the virtual reference line;
An input-side reflecting surface that is provided on the virtual reference straight line and reflects the incident light incident along the virtual reference straight line so as to be incident obliquely as read light on the reflective spatial light modulator;
An output-side reflecting surface provided on the virtual reference straight line, for reflecting the read light modulated by the reflective spatial light modulator and reflected obliquely and outputting the reflected light as outgoing light along the virtual reference straight line; With
The reflective spatial light modulator comprises an element reflecting surface for reflecting the reading light from the input-side reflecting surface;
The input-side reflecting surface and the output-side reflecting surface are separated by a distance L along the virtual reference line, and the element reflecting surface is a distance h in a direction perpendicular to the virtual reference line from the virtual reference line. The input side reflection surface, the output side reflection surface, and the element reflection surface are inclined by angles φ1, φ2, and φ3, respectively, with respect to the direction in which the virtual reference straight line extends, The distances L and h and the angles φ1, φ2, and φ3 satisfy the expressions (1) and (2),
The optical processing apparatus, wherein the first lens performs a Fourier transform on the emitted light output from the another spatial light modulator .

A pentagonal prism shape having first to fifth side surfaces in this order, the first side surface and the second side surface are connected to each other at 90 °, and the second side surface and the third side surface are 90 ° to each other. The third side surface and the fourth side surface are connected to each other at 90 ° −φ2, the fourth side surface and the fifth side surface are connected to each other at 180 ° + φ1 + φ2, A coupling prism in which the side surface of 5 and the first side surface are connected to each other at 90 ° -φ1;
A reflective spatial light modulation element having an element reflection surface is bonded to the second side surface so that the element reflection surface extends parallel to the second side surface;
The virtual reference straight line passes through the first side surface and the fifth side surface, the fifth side surface and the fourth side surface are separated by a distance L along the virtual reference straight line, and the element reflection surface is the virtual reference line. The fifth side surface, the fourth side surface, and the element reflection surface are separated from the straight line by a distance h in a direction perpendicular to the virtual reference straight line, and an angle φ1 with respect to the direction in which the virtual reference straight line extends. , Φ2 and φ3, and the coupling prism is made into a virtual reference straight line so that the distances L and h and the angles φ1, φ2 and φ3 satisfy the following expressions (1 ′) and (2 ′): Placed against

Read light is incident on the fifth side surface along the virtual reference straight line ,
The refractive index of the coupling prism is m,
The reflective spatial light modulation element modulates the reading light incident at a convergence angle in the range of 0 to α, and emits the predetermined component at a divergence angle in the range of 0 to β.
When the readout light incident on the reflective spatial light modulator is convergent light, α takes a positive value, and when divergent light, α takes a negative value and is emitted from the reflective spatial light modulator. When the predetermined component of the readout light is divergent light, β takes a positive value, and when it is convergent light, β takes a negative value,
The predetermined component is a diffraction component having a diffraction order of 1 or more and n (n is a natural number greater than 0), δ is a diffraction angle of the n-order diffracted light, and α and β are wavelengths λ of the incident light, A coupling prism characterized by satisfying the following equations (9 ′) and (10 ′) for the lattice constant d of the smallest lattice pattern that can be displayed on the reflective spatial light modulator : how to use.

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