Reflective spatial light modulator, optical observation device and optical irradiation device
A reflective spatial light modulator includes a perovskite-type electro-optic crystal having a relative permittivity of 1,000 or higher, a light input and output unit disposed on an input surface of the electro-optic crystal and including a first electrode through which input light is transmitted, a light reflecting unit including a plurality of second electrodes disposed on a rear surface of the electro-optic crystal and reflects the input light toward the light input and output unit, a drive circuit including a plurality of drive electrodes respectively corresponding to the plurality of second electrodes and for applying an electric field to a part between the first electrode and the second electrode by inputting an electrical signal to each of the plurality of drive electrodes, and a plurality of bumps which are disposed such that the plurality of second electrodes and the plurality of drive electrodes are electrically connected to each other.
1. A reflective spatial light modulator for modulating input light and outputting modulated light that has been subjected to modulation, the reflective spatial light modulator comprising:
a perovskite-type electro-optic crystal having a relative permittivity of 1,000 or higher and including an input surface to which the input light is input and a rear surface which is a surface on an opposite side of the input surface;
a light input and output unit disposed on the input surface of the electro-optic crystal and including a first electrode through which the input light is transmitted;
a light reflecting unit including a plurality of second electrodes disposed on the rear surface of the electro-optic crystal and reflects the input light toward the light input and output unit;
a drive circuit including a plurality of drive electrodes respectively corresponding to the plurality of second electrodes in the light reflecting unit and for applying an electric field between the first electrode and the second electrode by inputting an electrical signal to each of the plurality of drive electrodes; and
an electrode connection portion including a plurality of bumps which is disposed such that the plurality of second electrodes and the plurality of drive electrodes corresponding to the plurality of second electrodes are electrically connected to each other,
wherein a propagation direction of the input light is parallel or perpendicular to one of two axes obtained by rotating two crystal axes about one remaining crystal axis of the electro-optic crystal at an angle other than 0° and 90°.
2. The reflective spatial light modulator according to claim 1 , further comprising:
a transparent substrate including a first surface to which the input light is input and a second surface which is a surface on the opposite side of the first surface,
wherein the second surface of the transparent substrate and the input surface of the light input and output unit face each other.
3. The reflective spatial light modulator according to claim 1 ,
wherein the first electrode is formed over the entire input surface.
4. The reflective spatial light modulator according to claim 1 ,
wherein in the light reflecting unit, the input light is reflected by the plurality of second electrodes.
5. The reflective spatial light modulator according to claim 1 ,
wherein the electro-optic crystal is a crystal of KTa 1−x Nb x O 3 (0≤x≤1), a crystal of K 1−y Li y Ta 1−x Nb x O 3 (0≤x≤1 and 0≤y≤1), or a PLZT crystal.
6. The reflective spatial light modulator according to claim 1 , further comprising:
a temperature controller configured to control a temperature of the electro-optic crystal.
7. An optical observation device comprising:
a light source configured to output the input light;
the reflective spatial light modulator according to claim 1 ;
an optical system configured to irradiate a target with modulated light output from the reflective spatial light modulator; and
a light detector configured to detect light output from the target.
8. An optical irradiation device comprising:
a light source configured to output the input light;
the reflective spatial light modulator according to claim 1 ; and
an optical system configured to irradiate a target with modulated light output from the reflective spatial light modulator.