A passive long-wavelength infrared microscope with a highly sensitive phototransistor.
A passive scanning confocal microscope in the long-wavelength infrared (LWIR) region has been developed for sensitive imaging of spontaneous LWIR radiation by utilizing an ultrahighly sensitive detector, called the charge-sensitive infrared phototransistor (CSIP). The microscope consisted of room-temperature components including a Ge objective lens and liquid helium temperature components including a confocal pinhole, Ge relay lenses, and CSIP detector. With the microscope, thermal radiation (wavelength of 14.7 microm) spontaneously emitted by the object was studied with a spatial resolution of 25 microm. Clear passive LWIR imaging pictures were obtained by scanning a sample consisting of glass, Al foil, Ag paste, and Au. Clear passive LWIR image was also obtained even when the sample surface was covered by a GaAs or Si plate. This work suggests usefulness of CSIP detectors for application of passive LWIR microscopy.
Kajihara
Yusuke
Y
Department of Basic Science, The University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan.
Komiyama
Susumu
S
Nickels
Patrick
P
Ueda
Takeji
T