Abstract: An illumination optical system to be disposed between a light source and a specimen comprises, in order from a light source side, a collector lens, a diffusing plate having a diffusing surface, a light source image projecting lens, and a condenser lens. A field stop is arranged between the diffusing plate and the light source image projecting lens, and an aperture stop is arranged between the light source image projecting lens and the condenser lens. The illumination optical system can attain an ideal numerical aperture and provide uniform and bright illumination light over a predetermined area upon diffusion characteristics on the diffusing surface being adjusted.

Abstract: A microscope optical system includes an illumination system for radiating light from a light source toward an object, an objective lens and an imaging lens for forming an image of the object, and an observing optical system for observing the image or a photographing optical system for photographing the image. This microscope optical system is designed so that a relay system constructed as an afocal system with a first positive lens unit and a second positive lens unit is disposed between the objective lens and the imaging lens, and an element for pupil modulation can be disposed at a position nearly conjugate with the pupil of the objective lens relayed by the relay system, satisfying a condition:f2/f1>1.2where f1 is the focal length of the first positive lens unit and f2 is the focal length of the second positive lens unit.

Abstract: An automatic focus detection device for microscopes includes an optical system for forming an image of a sample; an image sensor for photoelectrically converting an optical image derived from the optical system; a device for storing image data such that an electric signal obtained from the image sensor is converted from analog to digital form and for processing the image data to compute contrast values; a device for comparing the contrast values; a device for moving an objective lens or a stage for the sample; and a device for storing the position of the objective lens or the stage.

Abstract: The present invention provides a novel culture which belongs to Actinoplanes (Actinoplanes sp. FERM BP-3832). This culture is capable of producing rapamycin more than ten times efficiently than the cultures which have been reported (e.g., Streptomyces hygroscopicus ATCC 29253). The present invention provides a process for the production of rapamycin which comprises cultivating Actinoplanes sp. FERM BP-3832 and thereafter isolating rapamycin from the fermentation mixture.

Abstract: A gas turbine combustor suppresses the generation of NOx by mixing a fuel and air homogeneously. A pilot nozzle is provided at the center of the gas turbine combustor. A plurality of main nozzles surround the pilot nozzle. A diverging cone projects from the vicinity of the injection port of the pilot nozzle such that the flame from the main nozzles is sustained by the pilot nozzle and NOx is suppressed. The main nozzles can be provided upstream of the injection port of the pilot nozzle in which case an annular premixing nozzle having a throttled exit end is disposed downstream of the main nozzles. The main nozzle may also be in the form of a fuel nozzle having a plurality of tubes, a gaseous fuel being injected through one of the tubes, and liquid fuel being injected into the annular premixing nozzle through the other of the tubes so that the liquid fuel is atomized to mix the fuel and air homogeneously.