Asahi Kogaku Kogyo Kabushiki Kaisha

Casio Computer Co., Ltd.

Kubota Corporation

Sanki Engineering Co., Ltd.

Kubota Air Conditioner Ltd.

Masakazu Yamagata

Ryota Ogawa

Yasuyuki Tejima

Nobutaka Minefuji

Shuzo Akita

Masaaki Shinohara

Tsuguaki Uemura

Washer media are disposed in an air inlet and an air outlet of a water spray chamber. A basic unit is formed by first stage nozzles from which spraying water that reaches the inlet washer media is sprayed in the reverse direction to an air flow; a water storage tank for receiving spraying water, located in the lower position of the water spray chamber; and a circulating water supply system that circulates the circulating water in the water storage tank to the first stage nozzles. Second stage nozzles from which spraying water directed against the outlet washer media is sprayed in the forward direction to the air flow are disposed in approximately the same positions as the first stage nozzles. There is also provided a supplementary water supply system for supplying supplementary water to the second stage nozzles.

Air washer

A projection lens assembly having an imaging lens group, including a first lens group having a positive refractive power, a second lens group having a positive refractive power, and a Fresnel lens group having a positive refractive power and at least one Fresnel lens surface, in this order from the enlargement side. The projection lens assembly satisfies the relationships 1.4&lt;f.sub.1 /f&lt;2.8, and 1.5&lt;f.sub.2 /f&lt;6.0. In these relationships, f represents the focal length of the whole lens system, f.sub.1 the focal length of the first lens group, and f.sub.2 the focal length of the second lens group.

Projection lens assembly and projector

An endoscope objective lens system is disclosed in which the lens disposed just in front of a diaphragm stop in the lens system is a divergent lens having a concave surface on the image side and the convergent lens disposed immediately after the diaphragm stop is in the form of a convergent lens unit comprising, in order from the object side, a first optical element and a second optical element. The two optical elements are made of optical materials having different Abbe numbers (.nu. values) in such a way that the relation .nu..sub.2 &lt;.nu..sub.3 is satisfied, where .nu..sub.2 is the Abbe number of the first optical element and .nu..sub.3 is the Abbe number of the second optical element.

Endoscope objective lens system

A viewing optical system for use with an endoscope and which permits a substantial reduction in the size of the objective lens system at the object end of the device, making the endoscope more maneuverable. The optical system includes an objective lens unit forming a curved image plane conjugate with the object plane and an optical-fiber image guide having one end surface curved to substantially conform to the image plane.

Viewing optical system for use with endoscope

A telephoto lens system which can focus down to unity magnification comprising two lens groups that are displaced during focusing. The front lens group of positive refractive power has five or six elements, namely, a positive lens, a positive meniscus lens, a negative lens, a lens element with a slightly negative refractive power and a positive lens. The rear lens group of negative refractive power has three elements, namely, a positive, a negative and a positive lens element. Additionally, there are four numerical conditions on focal lengths and radii of curvature.

Telephoto lens system capable of closeup shooting

Herein disclosed is a close-up photographic lens system comprising a first lens group disposed on the object side and having a positive refractive power and a second lens group disposed on the image side and having a negative refractive power. The first lens group is movable relative to the second lens group, thereby focusing the object from an infinite distance to a close-up distance with respect to the lens system. The lens system meets the following conditions.

Close-up lens system

A lens system including five lenses which are, in order from the object, a first single positive meniscus lens, a second single positive meniscus lens, a third single negative lens, a fourth single meniscus lens and a fifth single positive lens. The overall lens system has an aperture ratio of 1:2.8 and a viewing angle of approximately 24.degree.. A stop diaphragm is disposed at a rear portion of the overall lens system. Operations are well compensated for by providing the various lenses with parameters as specified for the preferred embodiments.

Growing community of inventors

Tokyo, Japan

Masakazu Yamagata