Optical microscope

#1. Field of Invention

#This invention relates to an optical microscope; and more particularly, to an improvement thereof which results in reduced background light and achieves high S/N ratio in scanning type or reflecting type confocal optical microscopes.

#2. Description of the Prior Art

#FIG. 1 is a drawing depicting a conventional optical microscope.

#FIG. 2 is a drawing depicting an illustrative embodiment of the invention .

#FIG. 3 is a drawing depicting use of a cover glass as the quarter wavelength plate.

#In FIG. 2, the same symbols used for the same parts in the system of FIG. 1 are used in the remaining figures and will not be further discussed hereat for sake of clarity of description. Mirrors 22, 25 and 26 are provided to change the direction of a light beam. A laser light beam is introduced into mirror 22 via FC connector 21. The laser light beam is introduced into FC connector 21 through an optical fiber, not shown, from a laser source, not shown. An arc light source or a lamp may be used in place of the laser as a light source. In addition, a light source may be located directly in place of the FC connector and not be limited to the light source introduction method using an optical fiber connected to the FC connector.

#Collimating lens 23 is a lens for changing the reflected light from mirror 22 into parallel light beam. ND filter 24 is a beam attenuating filter used for suitably controlling the quantity of light to be irradiated on sample 8. Collimating lens 23 and ND filter 24 are arranged between mirrors 22 and 25. In addition, polarizer 2 is located between mirrors 25 and 26.

#Micro lens disk 27 (in FIG. 2, the left half of the micro lens arrangement is omitted for clarity of description) is mounted above and in parallel with a pinhole array disk 4 in a manner as though polarized beam splitter 3 were sandwiched by microlens disk 27 and pinhole array disk 4. Pinhole array disk 4 is a disk in which a plurality of very small apertures are located in a predetermined pattern (This type of disk is called a Nipkow disk). Micro lenses arranged in the same pattern as that of the pinholes in the pinhole array disk 4 are mounted on micro lens disk 27. The micro lens has the effect of enhancing the light utilization factor. Approximately 20,000 micolenses and pinholes are arranged in micro lens disk 27 and pinhole array disk 4, respectively, and forming helical patterns. Laser light beam from mirror 26 illuminates an area, for example, of 10 mm by 7 mm on pinhole array disk 4. The two disks 27 and 4 are constructed to be concurrently rotated by a motor, not shown.