Optical module and light exposure device

Patent metadata

Field	Value
Publication number	US-9784980-B2
Application number	US-201414782015-A
Country	US
Kind code	B2
Filing date	Mar 25, 2014
Priority date	Apr 5, 2013
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

An optical module ( 1 A) includes a polarization beam splitter ( 10 A), polarization elements ( 20 and 40 ) having nonreciprocal optical activity and respectively arranged on an optical path of a first polarization component (L 2 ) transmitted through a light splitting surface ( 11 ) in irradiation light (L 1 ) and an optical path of a second polarization component (L 4 ) reflected in the light splitting surface ( 11 ), a first reflective SLM ( 30 ) that modulates and reflects a first polarization component (L 2 ) passing through the first polarization element ( 20 ), and a second reflective SLM ( 50 ) that modulates and reflects the second polarization component (L 4 ) passing through the second polarization element ( 40 ). First modulation light (L 3 ) passing through the polarization element ( 20 ) again and then reflected by the light splitting surface ( 11 ) and second modulation light (L 5 ) passing through the polarization element ( 40 ) again and then transmitted through the light splitting surface ( 11 ) are combined with each other.

First claim

The invention claimed is:

1. An optical module for modulating irradiation light output from a light source to generate modulation light, the optical module comprising:
a polarization beam splitter including a light splitting surface configured to reflect an s-polarization component included in the irradiation light and transmit a p-polarization component;
a first polarization element having nonreciprocal optical activity to rotate a polarization plane, and arranged on an optical path of a first polarization component transmitted through the light splitting surface in the irradiation light;
a first reflective spatial light modulator configured to modulate the first polarization component passing through the first polarization element to generate first modulation light, and reflect the first modulation light to the first polarization element;
a second polarization element having nonreciprocal optical activity to rotate a polarization plane, and arranged on an optical path of a second polarization component reflected by the light splitting surface in the irradiation light; and
a second reflective spatial light modulator configured to modulate the second polarization component passing through the second polarization element to generate second modulation light, and reflect the second modulation light to the second polarization element,
wherein the first modulation light passing through the first polarization element again and then reflected by the light splitting surface and the second modulation light passing through the second polarization element again and then transmitted through the light splitting surface are combined with each other, output from the polarization beam splitter.

2. The optical module according to claim 1 ,
wherein the first and second reflective spatial light modulators are liquid crystal types, and
an alignment direction of liquid crystal of the first reflective spatial light modulator and an alignment direction of liquid crystal of the second reflective spatial light modulator are orthogonal to each other.

3. The optical module according to claim 1 , further comprising:
a polarization element having reciprocal optical activity, and arranged on an optical path between the polarization beam splitter and the first reflective spatial light modulator or on an optical path between the polarization beam splitter and the second reflective spatial light modulator.

4. A light irradiation apparatus, comprising:
the optical module according to claim 1 ;
a light source configured to output the irradiation light to the optical module; and
a light-guiding optical system configured to irradiate an irradiation target with the modulation light output from the optical module.

5. An optical module for modulating irradiation light output from a light source to generate modulation light, the optical module comprising:
a first polarization beam splitter including a light splitting surface configured to reflect an s-polarization component and transmit a p-polarization component, and configured to receive first irradiation light including the p-polarization component;
a first polarization element having nonreciprocal optical activity to rotate a polarization plane, and arranged on an optical path of the first irradiation light transmitted through the light splitting surface of the first polarization beam splitter;
a first reflective spatial light modulator configured to modulate the first irradiation light passing through the first polarization element to generate first modulation light, and reflect the first modulation light to the first polarization element;
a second polarization beam splitter including a light splitting surface configured to reflect the s-polarization component and transmit the p-polarization component, and configured to receive second irradiation light including any one of the s-polarization component and the p-polarization component;
a second polarization element having nonreciprocal optical activity to rotate a polarization plane, and arranged on an optical path of the second irradiation light subjected to one of transmission and reflection in the light splitting surface of the second polarization beam splitter; and
a second reflective spatial light modulator configured to modulate the second irradiation light passing through the second polarization element to generate second modulation light, and reflect the second modulation light to the second polarization element,
wherein the first modulation light passes through the first polarization element again and then is reflected in the light splitting surface of the first polarization beam splitter, and the second modulation light passes through the second polarization element again and then reaches the light splitting surface of the first polarization beam splitter through the other of the transmission and the reflection in the light splitting surface of the second polarization beam splitter, and
the first and second modulation light is combined, and output from the first polarization beam splitter.

6. The optical module according to claim 5 , further comprising:
an optical path length adjustment element provided on an optical path between the first polarization beam splitter and the first reflective spatial light modulator.

7. The optical module according to claim 5 , further comprising:
a polarization element having reciprocal optical activity and provided on an optical path between the first polarization beam splitter and the second polarization beam splitter.

8. A light irradiation apparatus, comprising:
the optical module according to claim 5 ;
at least one of light source configured to output the first and second irradiation light to the optical module; and
a light-guiding optical system configured to irradiate an irradiation target with the modulation light output from the optical module.

9. The light irradiation apparatus according to claim 8 , further comprising:
a first spectroscopic element arranged on an optical path of the first irradiation light, and configured to split the first irradiation light based on wavelength components or polarization components; and
a second spectroscopic element arranged on an optical path of the second irradiation light, and configured to split the second irradiation light based on wavelength components or polarization components.

10. The light irradiation apparatus according to claim 8 , further comprising:
a ½-wavelength plate,
wherein the ½-wavelength plate is arranged on at least one of an optical path of the first irradiation light and an optical path of the second irradiation light.

Assignees

• Hamamatsu Photonics Kk

Inventors

• Inoue Takashi
• Terada Hirotoshi

Classifications

• G02B27/283

  used for beam splitting or combining · CPC title

• G02B27/1006 Primary

  for splitting or combining different wavelengths (G02B27/1086, G02B27/141 take precedence) · CPC title

• G02B27/286

  for controlling or changing the state of polarisation, e.g. transforming one polarisation state into another (G02B5/3083 takes precedence; light guide coupling means utilising polarising elements G02B6/34) · CPC title

• B23K26/0648

  comprising lenses · CPC title

• B23K26/0676

  into dependently operating sub-beams, e.g. an array of spots with fixed spatial relationship or for performing simultaneously identical operations · CPC title