Takaoka Eiko

YCa4O(BO3)(3) has been found to be 90degrees phase-matchable for type-1 SHG at 0.8325 mum along z. In addition, we report the new experimental data on the phase-matching properties of YCa4O(BO3)(3) together with the improved Sellmeier's equations that reproduce well our new experimental results.

AgGaS2 has been found to be 90° phase matchable at 192 °C for sum-frequency mixing between the output of the KTP parametric oscillator at 3.2627 μm and its pump source at 1.0642 μm. The thermooptic dispersion formula that can be used for good reproduction of the temperature-dependent phasematching conditions thus far reported in the literature as well as our new data for second-harmonic generation of a CO2 laser and its harmonics at 1.7652-5.2955 μm is presented. © 1999 Optical Society of America.

AgCa(1-x)ln(x)Se(2) with x = 0.474 was found to be 90 degrees phase matchable for third-harmonic generation of CO2 laser wavelengths 9.2714-10.5910 mu m by means of temperature tuning. Sellmeier equations and the thermo-optic constant for this crystal are presented. (C) 1999 Optical Society of America. OCIS codes: 160.6840, 140.3470, 190.4970.

The high accuracy Sellmeier equations of GaSe were constructed from the phase-matching conditions for harmonic generation of a CO2 laser and published refractive indices. The high accuracy thermo-optic dispersion formula is also presented.

The thermooptic constants of AgGaSe2 have been measured at 2.052, 3.3913, 5.2955, and 10.5910 mu m. These results combined with the literature values were used to construct the thermooptic dispersion formula which correctly reproduces the temperature dependent phase-matching conditions for second-harmonic generation (SHG) and sum-frequency generation (SFG) of a CO2 laser as well as the thermally induced lensing effects for the 2.05 mu m pumped parametric oscillators (OPO).

90 degrees phase-matched parametric oscillation up to 4.3 mu m was obtained in the undoped KTiOAsO4 (KTA) crystal by pumping with the 1.928 mu m output of a KTiOPO4 (KTP) parametric oscillator pumped by an Nd:YAG laser at 1.064 mu m. The oscillator is continuous tunable hom 3.4 to 4.3 mu m. The improved Sellmeier's equations are presented.

In the list processing language, dynamic memory management is indispensable, and hence various methods have been proposed. In one such method, the object is discriminated according to its life, time and garbage collection (GC) is applied efficiently to the unnecessary object, based on a preset “threshold.” A problem is how the threshold should be set in order to realize the most efficient GC. This paper points out that the threshold that realizes the highest efficiency depends on the application to be executed, and proposes the technique of adaptive garbage collection (AGC). An experiment toward its implementation is reported. AGC is a kind of GC which adjusts the threshold dynamically according to memory use, so that efficient operation is realized for a variety of applications. Experiments aiming at the realization of AGC show that applications have their own pace in consuming the memory, and the optimal value of the threshold is related to that pace. It is seen also that the memory‐consuming pace of the application is related closely to the data in the interpreter, leading to the definition of the useful parameter for realizing the efficient AGC. Copyright © 1995 Wiley Periodicals, Inc., A Wiley Company