FAR INFRARED IMAGING DEVICE AND IMAGING METHOD USING SAME
Provided are a far infrared imaging device that illuminates a specimen with far infrared light and detects an image of the specimen, which is a device capable of imaging a specimen speedily without using a high-power light source and without generating damage or a non-linear phenomenon in the specimen as a target to be imaged and a method using the same. A specimen is illuminated with the far infrared light in a line shape or in a shape of a plurality of points arranged in line on the specimen; and an image of the specimen is detected while moving the specimen in a direction perpendicular to the line illuminated by the far infrared light. The far infrared light is emitted by applying pulsed pump light from a femtosecond pulse light source to the far infrared light emission element.
1 . A far infrared imaging device that irradiates a specimen with far infrared light and detects an image of the specimen, comprising:
a far infrared light emission element that emits the far infrared light;
an illumination optical system that makes the far infrared light in a line shape or in a shape of a plurality of points arranged in line on the specimen; and
an image formation optical system that detects the image while moving the specimen in a direction perpendicular to the line illuminated by the far infrared light.
2 . The far infrared imaging device according to claim 1 , wherein the far infrared light is emitted by applying pulsed pump light from a femtosecond pulse light source to the far infrared light emission element.
3 . The far infrared imaging device according to claim 2 , wherein the far infrared light emission element comprises a photoconductive switch, and current flows through the photoconductive switch in a direction corresponding to the longitudinal direction of the linear illuminated region on the specimen.
4 . The far infrared imaging device according to claim 1 , wherein the far infrared light emission element is a quantum-cascade laser.
5 . The far infrared imaging device according to claim 1 , wherein the far infrared light emission element is a Schottky barrier diode.
6 . The far infrared imaging device according to claim 1 , wherein the image formation optical system comprises a far infrared light detection element using a one-dimensional array of photoconductive switches.
7 . The far infrared imaging device according to claim 3 , wherein the image formation optical system comprises a far infrared light detection element using a one-dimensional array of photoconductive switches.
8 . The far infrared imaging device according to claim 1 , wherein the image formation optical system comprises a Schwarzschild optical system element.
9 . The far infrared imaging device according to claim 1 , wherein the image formation optical system comprises combination of off-axis paraboloid mirrors.
10 . The far infrared imaging device according to claim 1 , wherein the image formation optical system is a projection optical system having a magnification larger than 1.
11 . An imaging method using a far infrared imaging device that irradiates a specimen with far infrared light and detects an image of the specimen, the method comprising the steps of:
illuminating the specimen with the far infrared light in a line shape or in a shape of a plurality of points arranged in line on the specimen; and
detecting the image while moving the specimen in a direction perpendicular to the line illuminated by the far infrared light.
12 . The imaging method according to claim 11 , wherein the far infrared light is emitted by applying pulsed pump light from a femtosecond pulse light source to a far infrared light emission element.
13 . The imaging method according to claim 12 , wherein the far infrared light emission element comprises a photoconductive switch, and the far infrared imaging device used is configured to let current flow through the photoconductive switch in a direction corresponding to the longitudinal direction of the linear illuminated region on the specimen.
14 . The far infrared imaging device according to claim 1 , wherein the image formation optical system comprises a far infrared light detection element with a one-dimensional detector array formed on a curved surface.