Newly developed optical instruments in the mass-productive lens factory are presented. Each instrument listed below is for 1) Newton testing, 2) optical axis centering, 3) optical thin film monitoring, 4) image distribution measuring.

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A new lens testing method is described to judge the lens performance speedily and objectively. In this method, the MTF values of whole angle of view at a special frequency are displayed on a color cathode-ray tube simultaneously. The most important feature of the method is to save labor of tests. Results of ITV lenses testing are described.

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The new deciding method of tolerance of decentered optical systems is described. This method consists of two steps, the first step which decides temporary tolerance and the second step which decides final tolerance by simulating prototypes using Monte-Carlo method.

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Abelès-type refractometer of determining the refractive index of a thin film is discussed. A rotary encoder and a lock-in-amplifier are used for the measurement of the Abelès angle. The refractive index between 1.3 and 4.0 can be measured to an accuracy range of about 0.002 in the 380-800 nm wavelength region. An improved measuring method is also discussed.

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A new aspheric lens grinding machine was developped.
The lens is ground with a diamond tool whose location is numerically controlled precisely (1 μm on horizontal axis, 1/6 μm on vertical axis). Surface profiles are measured by a tracing stylus profilometer with the standard deviation of ±0.4 μm. A Schmidt corrector plate of 400 mm aperture for the 700 mm reflector of Kyoto University was measured by this instrument using together with Hartmann method.
Now, a step toward improvement is taken for highly precise grinding mechanism.

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As one method for fabricating the aspheric optical surfaces the cam system was first introduced in about 1950.
Ellipsoidal and paraboloidal mirrors for the infrared spectrometer, paraboloidal mirrors for the sky projector, paraboloidal mirrors for the large solar-furnace, and the other aspheric surfaces were fabricated by the mechanism of the cam. The lever system with zero-method was also employed in this mechanism.
Now we came up to the step to introduce some mechanism for compensating the abrasion loss of the tool.

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This paper deals with the polishing operation of Si single crystal wafers. Scratches made on Si wafers were microscopically observed and then the fundamental polishing mechanisms were discussed. From the results of polishing experiments by using various polishers, characteristics are investigated and a new polishing wheel was developed. It was shown that the wheel was available to make the fine surfaces of Si wafers.

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Zirconum oxides is popularly used as the material for optical coatings, especially for multi-layer anti-reflection coatings. It is known that in these coatings, “KUMORI”something like SHIROYAKE and“absorption”phenomena apear in some cases. We found that these phenomena are caused by the interaction between Zirconum oxide films and optical glasses. Based on the relation of these phenomena with the kind of optical glasses and with the way of the processing, we infered the causes and mechanism of these phenomena.

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Methods of holding optical parts and effects of thermal deformation of tools, which are important problems in the process of making ultra high precision optical parts, are examined by using holographic techniques. As a result, the convensional process established in workshop is proves to be reasonable.

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