Search

EP-4737992-A1 - SPATIAL LIGHT MODULATION ELEMENT, OPTICAL UNIT, AND LIGHT PROCESSING DEVICE

EP4737992A1EP 4737992 A1EP4737992 A1EP 4737992A1EP-4737992-A1

Abstract

A spatial light modulation element (100) comprises: an optical member (110) on which processing light traveling in a Z direction is incident as incident light and which is formed using a ferroelectric material having light transmittance; positive and negative electrodes (120, 125) arranged on an arrangement surface (113) of an optical member (110) in an X direction; and wirings (a positive wire (130) and a ground wire (135)) through which a voltage is applied to the positive electrode (120) so as to create a potential difference between the positive and negative electrodes (120, 125). When the potential difference is generated between the positive and negative electrodes (120, 125), a refractive index in the optical member (110) changes in the X direction.

Inventors

  • OKAZAKI, MASAHIDE

Assignees

  • NIKON CORPORATION

Dates

Publication Date
20260506
Application Date
20230628

Claims (20)

  1. A spatial light modulation element that modulates incident light and exits the light, comprising: an optical member on which the incident light is incident traveling along a first axis and which is formed using a ferroelectric material having light transmittance; first and second electrodes that are arranged on a surface of the optical member along a second axis intersecting with the first axis; and a wiring through which a voltage is applied to at least one of the first and second electrodes so as to create a potential difference between the first and second electrodes.
  2. The spatial light modulation element according to Claim 1, wherein the incident light is modulated by the potential difference between the first and second electrodes.
  3. The spatial light modulation element according to Claim 1 or 2, wherein the first and second electrodes are adjacent to each other in a direction along the second axis.
  4. The spatial light modulation element according to any one of Claims 1 to 3, wherein the surface of the optical member intersects with a third axis that intersects with the first axis and the second axis.
  5. The spatial light modulation element according to any one of Claims 1 to 4, wherein a refractive index in the optical member changes along the second axis as the voltage is applied from the wiring.
  6. A spatial light modulation element that modulates incident light and exits the light, comprising: an optical member on which the incident light is incident traveling along a first axis and which is formed using a ferroelectric material having light transmittance; and first and second electrodes that are arranged on a surface of the optical member along a second axis intersecting with the first axis, wherein when a potential difference is generated between the first and second electrodes, a refractive index in the optical member changes along the second axis.
  7. The spatial light modulation element according to Claim 5 or 6, wherein the refractive index differs for each of a position in the optical member where the first electrode is provided in a direction of the second axis and a position in the optical member where the second electrode is provided in the direction of the second axis.
  8. The spatial light modulation element according to any one of Claims 5 to 7, wherein a diffraction grating having a pitch direction along the second axis is generated in the optical member as the refractive index changes in the optical member.
  9. The spatial light modulation element according to Claim 8, wherein a plurality of electrodes are provided along the second axis in a first region on the surface of the optical member to generate the diffraction grating, a plurality of electrodes are provided along the second axis in a second region adjacent to the first region on the surface of the optical member in a direction along the first axis to generate the diffraction grating, and the plurality of electrodes include the first and second electrodes.
  10. The spatial light modulation element according to Claim 9, wherein a first diffraction grating generated by the plurality of electrodes in the first region is different in a phase of a refractive index change from a second diffraction grating generated by the plurality of electrodes in the second region.
  11. The spatial light modulation element according to Claim 10, wherein the incident light incident on the optical member is diffracted by Bragg diffraction at the first diffraction grating, and the phase of the refractive index change of the second diffraction grating is equal to the phase of the refractive index change of the first diffraction grating in a direction orthogonal to a traveling direction of diffracted light that is diffracted by the Bragg diffraction.
  12. The spatial light modulation element according to any one of Claims 5 to 11, wherein the incident light incident on the optical member passes, in a direction intersecting with the second axis, through a region in the optical member where the refractive index changes.
  13. The spatial light modulation element according to any one of Claims 1 to 12, wherein the optical member includes a first polarization part extending along the first axis, and a second polarization part extending along the first axis and polarized in a direction different from that of the first polarization part, the second polarization part being located adjacent to the first polarization part in a direction along the second axis.
  14. The spatial light modulation element according to Claim 13, wherein the first and second electrodes are provided at a portion on the surface of the optical member where the first polarization part is located.
  15. The spatial light modulation element according to Claim 14, wherein an electric field is generated in the first polarization part, directed from the first electrode toward the second electrode.
  16. The spatial light modulation element according to Claim 15, wherein a refractive index differs for each of a position in the optical member where the first electrode is provided in a direction of the second axis and a position in the optical member where the second electrode is provided in the direction of the second axis.
  17. The spatial light modulation element according to any one of Claims 14 to 16, further comprising third and fourth electrodes that are provided at a portion on the surface of the optical member where the second polarization part is located.
  18. The spatial light modulation element according to any one of Claims 13 to 16, wherein the optical member includes a third polarization part extending along the first axis and polarized in a direction different from that of the first polarization part, the third polarization part being located adjacent to the first polarization part on a side opposite to the second polarization part.
  19. The spatial light modulation element according to Claim 18, wherein the first electrode is provided at a position on the surface of the optical member straddling the first polarization part and the third polarization part, and the second electrode is provided at a position on the surface of the optical member straddling the first polarization part and the second polarization part.
  20. The spatial light modulation element according to Claim 18, further comprising: a third electrode that is provided at a position on the surface of the optical member on a side opposite to the second electrode of the second polarization part, wherein an electric field is generated in the first polarization part, directed from the first electrode toward the second electrode, and an electric field is generated in the second polarization part, directed from the third electrode toward the second electrode.

Description

TECHNICAL FIELD The present invention relates to a spatial light modulation element, an optical unit, and a light processing device. TECHNICAL BACKGROUND There have been known electro-optic spatial light modulation elements including a spatial light modulation element (for example, see Patent literature 1) in which electrodes are provided on one surface of an optical member that propagates light, and a spatial light modulation element in which electrodes are provided on both surfaces of an optical member that propagates light. These spatial light modulation elements are required to modulate light at high speed. PRIOR ARTS LIST PATENT DOCUMENT Patent literature 1: U.S. Patent No. 6,169,565 SUMMARY OF THE INVENTION A spatial light modulation element according to a first present invention modulates incident light and exits the light, comprising: an optical member on which the incident light is incident traveling along a first axis and which is formed using a ferroelectric material having light transmittance; first and second electrodes that are arranged on a surface of the optical member along a second axis intersecting with the first axis; and a wiring through which a voltage is applied to at least one of the first and second electrodes so as to create a potential difference between the first and second electrodes. A spatial light modulation element according to a second present invention modulates incident light and exits the light, comprising: an optical member on which the incident light is incident traveling along a first axis and which is formed using a ferroelectric material having light transmittance; and first and second electrodes that are arranged on a surface of the optical member along a second axis intersecting with the first axis, and when a potential difference is generated between the first and second electrodes, a refractive index in the optical member changes along the second axis. An optical unit according to the present invention comprises: the above-described spatial light modulation element; and an optical system on which diffracted light exited from the spatial light modulation element is incident, and the optical system includes a light-attenuating part that attenuates at least one of zeroth order diffracted light and diffracted light of an order different from the zeroth order diffracted light in the diffracted light. A light processing device according to the present invention processes an object using processing light emitted from a light source, comprising: the above-described optical unit; and an irradiation device that irradiates the object with the processing light emitted from the light source through the optical unit. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram showing a light processing device;FIG. 2 is a cross-sectional view showing a part of the light processing device;FIG. 3 is a schematic diagram of a spatial light modulation element unit as viewed from an incident plane;FIG. 4 is a front view of a lens array;FIG. 5 is a schematic configuration diagram showing a first modified example of the light processing device;FIG. 6 is a schematic configuration diagram showing a second modified example of the light processing device;FIG. 7 is a plan view of a spatial light modulation element according to a first embodiment;FIG. 8 is a plan view showing a state in which processing light is incident on the spatial light modulation element according to the first embodiment;FIG. 9 is a side view of the spatial light modulation element according to the first embodiment;FIG. 10 is a cross-sectional view of the spatial light modulation element according to the first embodiment;FIG. 11 is a plan view of a conventional spatial light modulation element;FIG. 12 is a side view of the conventional spatial light modulation element;FIG. 13 is a cross-sectional view of the conventional spatial light modulation element;FIG. 14 is a cross-sectional view showing a case where a distance between electrodes is narrowed in the conventional spatial light modulation element;FIG. 15 is a cross-sectional view showing a case where a distance between electrodes is widened in the conventional spatial light modulation element;FIG. 16 is a side view showing a first modified example of the spatial light modulation element according to the first embodiment;FIG. 17 is a side view showing a second modified example of the spatial light modulation element according to the first embodiment;FIG. 18 is a plan view of a spatial light modulation element according to a second embodiment;FIG. 19 is a plan view showing a state in which processing light is incident on the spatial light modulation element according to the second embodiment;FIG. 20 is a side view of the spatial light modulation element according to the second embodiment;FIG. 21 is a cross-sectional view of the spatial light modulation element according to the second embodiment;FIG. 22 is a plan view of a spatial light modulation e