A new in frared television (IRTV) fundus camera was employed to record and analyze eye movement. The IRTV fundus camera has a built-in target, and it can display fundus image with the target position on the retina. Therefore, it can record the movement of the fundus image associated with the movement of the subject's eye, and it can analyze the relation between the position of the fovea and that of the target on the retina. Furthermore, not only parallel movement but also rotatory movement of the eye can be analyzed from the movement of fUndus image. The sampling rate of the recording is 60Hz and the spatial resolution of the eye movement is less than 3 min. of arc of visual angle.
This method is applied to analyze the eye movement in congenital nystagmus patients and brings a lot of important knowledges to ophthalmology.
The present method of analysis, however, takes much time because of a man-machine system, and the fully automated system will be expected to be developed.

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A portable vacuum-pipe-less laser earth strainmeter has been designed and tested experimentally. The effects of barometric pressure change and atmospheric temperature change were successfully corrected by a digital compensator. Earth tides of 1×10^-8 in amplitude were clearly recorded by the strainmeter.

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A simple holographic interferometer for a phase object is presented. The object under test is placed close to a Ronchi grating. The light passing through the grating and the object is spatially divided into many diffraction components on the Fourier transform plane of a lens where a mask with two holes is inserted. The Oth order component passes through one of the two holes which is so small that the extention of the spectrum containing the object information is cut off. The 1st order component passes through the other hole which is large enough to transmit the complete object spectrum. These two waves become the reference wave and object wave for making the hologram and they take almost common path. Therefore, interferogram obtained in this method is stable against the external vibration. Since the carrier of the hologram has the same frequency as that of the grating, a high resolution photographic plate is not necessary.

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In order to simulate the process for figuring an aspheric optical surface using a small tool, a convolution model is introduced.
It is required to calculate a two dimensional convolution integral for the estimation of removal according to this model.
The algolism to deal with this operation by means of computer is presented and, using this algolism, a computer sirnulation for figuring a Schmidt corrector plate of 100mm aperture is executed.
It is concluded that this convolution model fits very well with the process of figuring the aspherical surface.

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