One of the dominant factors influencing the frequency aging of a crystal oscillator is the amount of surface irregularity left by polishing upon its crystal resonator. This paper deals with the refractive-index distribution of fused quartz as a measure of polished layer depth. It is found that the refractive-index distribution can be expressed by a combination of an exponential function and a linear function. The refractive index decreases exponentially from a surface value of 1.736 to a certain value at a depth of 50±10 Å and from it decreases linearly to the bulk value of 1.460 at a depth of 2000±200 Å.

The frequency of an AlGaAs semiconductor laser was stabilized by using the linear absorption spectrum of the 85Rb-D2 line. By controlling the injection current, the frequency stability of 3.0×10-10≧σ≧1.4×10-12 was obtained for 10 ms≦τ≦500 s. First observation of the saturated absorption spectrum of the 85Rb-D2 line is demonstrated, which can be used as a frequency reference to improve the frequency stability.

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Using a K-cut quartz SAW resonator, which is significantly less sensitive to thermalshock than an ST-cut quartz SAW resonator, we studied their design and made prototype SAW resonators w i t h cylindrical capsules.They have zero temperature coefficient of frequency at room temperature and have good properties for practical use.

-18.5° X-cut bar crystal blanks, 25.0×1.50×1.25 mm in size, were cut from different synthetic mother quartz. Defects in the bars were observed by light scattering tomography and X-ray traverse topography, Q-values were measured in the second overtone mode of 200 kHz in the air gap type holder and the maximum Q of 5.4×106 was obtained. Infrared absorption of the mother quartz, observed defects and the measured Q-values were discussed.