Optical inspection device, electromagnetic wave detection method, electromagnetic wave detection device, organism observation method, microscope, endoscope, and optical tomographic image generation device

Abstract

An optical inspection device 1, comprising a light generation means 2, a light irradiation means 3 irradiating an object to be inspected 4 with light generated from the light generation means 2 and a photodetection means 6 photoelectrically converting signal light obtained from the object to be inspected 4 through irradiation of light by the light irradiation means 3, and inspecting the object to be inspected 4 based on output from the photodetection means 6, wherein a light amplification means 5 amplifying signal light obtained from the object to be inspected 4 is provided. There is thus provided an optical inspection device capable of photoelectically converting signal light from the object to be inspected with high sensitivity and promptly with its inexpensive configuration without increasing the intensity of light with which the object to be inspected is irradiated and without using an expensive low-noise and high-sensitivity photodetector.

1 . An electromagnetic wave detection device, comprising
 a mode adjustment unit adjusting a mode condition of incident multimode electromagnetic waves;   an amplification unit amplifying the electromagnetic waves in which the mode condition has been adjusted output from the mode adjustment unit; and   a conversion unit converting the amplified electromagnetic waves output from the amplification unit to electrical signals,   wherein the mode adjustment unit is configured to adjust, by converting energy mode distribution, the incident multimode electromagnetic waves to of a mode substantially equal to an amplification spatial mode by the amplification unit.   
     
     
         2 . An electromagnetic wave detection device according to  claim 1 , wherein the mode adjustment unit is configured to reduce the number of spatial modes of incident electromagnetic waves. 
     
     
         3 . An electromagnetic wave detection device according to  claim 1 , wherein the mode adjustment unit is configured to vary an energy ratio among spatial modes of incident electromagnetic waves. 
     
     
         4 . An electromagnetic wave detection device according to  claim 1 , wherein the incident electromagnetic waves are light; and the mode adjustment unit is constituted by an optical waveguide. 
     
     
         5 . An electromagnetic wave detection device according to  claim 4 , wherein the optical waveguide is constituted by an optical fiber. 
     
     
         6 . An electromagnetic wave detection device according to  claim 5 , wherein the optical fiber is constituted by a tapered optical fiber. 
     
     
         7 . An electromagnetic wave detection device according to  claim 4 , wherein the optical waveguide is constituted by a refractive-index distribution type waveguide having nonuniform refractive-index distribution in a longitudinal direction of the optical waveguide or configured to adjust the mode condition by applying nonuniform stress distribution or nonuniform temperature distribution in a longitudinal direction of the optical waveguide. 
     
     
         8 . An electromagnetic wave detection device according to  claim 1 , wherein the incident electromagnetic waves are light; and the amplification unit is an optical fiber amplifier. 
     
     
         9 . An electromagnetic wave detection device according to  claim 8 , wherein the optical fiber amplifier is a rare-earth-doped optical fiber amplifier. 
     
     
         10 . An electromagnetic wave detection device according to  claim 9 , wherein the rare-earth-doped optical fiber amplifier is a rare-earth-doped fluoride optical fiber amplifier. 
     
     
         11 . An electromagnetic wave detection device according to  claim 8 , wherein the optical fiber amplifier is an optical fiber amplifier using stimulated Raman scattering effects. 
     
     
         12 . An electromagnetic wave detection device according to  claim 1 , wherein the incident electromagnetic waves are light; and the amplification unit is a semiconductor optical amplifier. 
     
     
         13 . An electromagnetic wave detection device according to  claim 1 , wherein the incident electromagnetic waves are light; and the amplification unit is an optical amplifier having dye. 
     
     
         14 . An electromagnetic wave detection device according to  claim 1 , wherein the amplification unit varies a gain depending on timing of incidence of the incident electromagnetic waves. 
     
     
         15 . An electromagnetic wave detection device according to  claim 1 , wherein the electromagnetic wave detection unit has, before the mode adjustment unit, a collecting unit collecting the incident electromagnetic waves and causing them to be incident on the mode adjustment unit. 
     
     
         16 . An electromagnetic wave detection device according to  claim 1 , wherein the electromagnetic wave detection unit has, before the mode adjustment unit, a plurality of collecting unit collecting the incident electromagnetic waves in parallel and causing them to be incident on the mode adjustment unit. 
     
     
         17 . An electromagnetic wave detection device according to  claim 16 , comprising a multiplex unit multiplexing a plurality of electromagnetic waves output from the plurality of collecting unit, wherein electromagnetic waves output from the multiplex unit are input to the mode adjustment unit. 
     
     
         18 . An electromagnetic wave detection device, comprising
 a plurality of mode adjustment unit respectively adjusting a mode condition of incident multimode electromagnetic waves which are incident in parallel;   a multiplex unit multiplexing a plurality of electromagnetic waves in which the mode condition has been adjusted output from the plurality of mode adjustment unit;   an amplification unit amplifying electromagnetic waves in which the plurality of electromagnetic waves have been multiplexed output from the multiplex unit; and   a conversion unit converting the amplified electromagnetic wave output from the amplification unit to electrical signals,   wherein the mode adjustment unit is configured to adjust, by converting energy mode distribution, the incident multimode electromagnetic waves to of a mode substantially equal to an amplification spatial mode by the amplification unit.   
     
     
         19 . An electromagnetic wave detection device, comprising
 a plurality of mode adjustment unit respectively adjusting a mode condition of incident multimode electromagnetic waves which are incident in parallel;   a plurality of amplification unit amplifying the plurality of electromagnetic waves in which the mode condition has been adjusted output from each of the mode adjustment unit; and   a parallel conversion unit converting the plurality of amplified electromagnetic waves output from each of the plurality of amplification unit to electrical signals in parallel,   wherein the mode adjustment unit is configured to adjust, by converting energy mode distribution, the incident multimode electromagnetic waves to of a mode substantially equal to an amplification spatial mode by the amplification unit.   
     
     
         20 . An electromagnetic wave detection method, comprising
 a mode adjustment step for adjusting a mode condition of incident multimode electromagnetic waves;   an amplification step for amplifying the electromagnetic waves in which the mode condition has been adjusted; and   a conversion step for converting the amplified electromagnetic waves to electrical signals,   wherein the adjustment step adjusts, by converting energy mode distribution, the incident multimode electromagnetic waves to of a mode substantially equal to an amplification spatial mode in the amplification step.   
     
     
         21 . An organism observation method, comprising
 an irradiation step for irradiating an organism with electromagnetic waves; and   a detection step for detecting, with the electromagnetic wave detection device according  claim 16 , electromagnetic waves to be detected obtained from the organism through irradiation with the electromagnetic waves,   wherein the organism is observed based on electrical signals obtained in the detection step.   
     
     
         22 . A microscope detecting electromagnetic waves to be detected from an object to be observed, comprising the electromagnetic wave detection device according to  claim 16 ,
 wherein the electromagnetic wave detection device is configured to detect the electromagnetic waves to be detected from the object to be observed.   
     
     
         23 . An endoscope detecting electromagnetic waves to be detected from a body cavity and observing the inside of the body cavity, comprising the electromagnetic wave detection device according to  claim 16 ,
 wherein the electromagnetic wave detection device is configured to detect the electromagnetic waves to be detected from the body cavity.