The method of using color gratings is proposed in the determination of a hill or a valley in the equal height contouring of an object surface by moire topography.
A triple color grating (red, blue and transparent in order) is used in the grating projection method. If the object surface is white, three kinds of typical moire color are obtained, and it can be determined, by observing the order of the moire color, whether the surface is convex or concave.

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Dependence of output power of a Xe laser on gas pressure, especially the enhancement effect of He or Ne as an additive is investigated for seven 5d-6p laser lines ranging from 2.03 to 5.58μm.
Increasing rate of laser output due to addition of He is largest at 2.03μm, then comes 2.65, 3.51, 3.37μmin order. The outputs of 3.11 and 5.58μm lines, which are little increased by addition of He, are increased by addition of Ne to Xe. Neither He nor Ne brings about increase in output of 3.27μm line. Outputs of laser lines without enhancement effect of He exhibit saturation at relatively low excitation power. Such difference between the effect of Ne and that of He depending on laser lines is qualitatively interpreted.
Also, variation of laser output as a function of the operation time due to gas clean-up is measured.

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A practical holographic interferometer developed for the measurement of a three-dimensional displacement distribution of a large-sized object, and an associated data processing to obtain the contour map of the displacement components are reported.
Since a twisted belt is much larger than the field of vision, partially observed sub-patterns are assembled into a whole interference fringe pattern. The fringe order numbers at corresponding point of three real images, reconstructed by a multiplexed hologram, are determined by careful interpretation of the fringe patterns under various loads. The instrumental relative error in measurement is about 13%, if the fringe order reading erroris 10%.
NTT's DEMOS-E service is used to smooth the holographic data and to obtain an equal displacement contour.

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