Basic studies on efficient parametric image-upconversion of 10<micrn>m band into the visible.

总结结果如下：1。以铯蒸气为非线性介质，6d、2D3/2能级为双光子共振能级，差频产生为转换过程的系统效率最高。结果表明，铯蒸汽室的温度有可能降低几百度，这表明了用热管炉以外的原理实现铯蒸汽室的可能性。根据理论计算，在上述系统中，无需任何缓冲气体即可实现共线相位匹配。在相位匹配条件下，计算了系统的接受角。在实验的基础上制作的鞍状蒸汽池已被测试并被发现是安全的。然而，电池允许蒸汽泄漏，因此正在建造第二个电池。对可能制约系统效率的双光子吸收进行了估算。综上所述，已经完成了10微米波段到可见光波长范围内有效的参数像上转换的大部分基础研究。可以在短时间内进行图像上转换的实验。

The summerized results are follows.1. The system utilizing cesium vapor as nonlinear medium, level 6d^2D 3/2 as Two-photon resonant level and difference frequency generation as conversion process will be the most efficient. The result indicates that lowering temperature of cesium vapor cell will be possible by several hundreds degree and it suggests the possibility of realizing a cell based on the principle other than heat pipe oven.2. In the above system collinear phase matching can be realized without any buffer gas according to theoretical calculation. Under the phase match condition the acceptance angle of the system is calculated.3. A secium vapor cell made on experimental basis has been tested and found to be safe. However, the cell permitted the leakage of the vapor, so that the second cell is being constructed.4. Two photon absorption which might restrict the efficiency of the system has been estimated.In conclusion, most of the basic studies on efficient parametric imageupconversion of 10<micrn>m band into the visible wavelength range has been accomplished. The experiment of the image upconversion can be performed shortly.