有什么奇怪的,美国livemore实验室用KTP做532nm激光器,输出功率都超过100W了
现在市场上见到的532nm的激光器,很多是用KTP做倍频的,输出功率在5W以上
况且衡量KTP的承受能力不是看实际功率，应该是看你的功率密度
光斑大小也有影响啊。
KTP在高温下（100℃）可以承受较高的功率密度。但是我觉得还是不能够跟LBO来比，毕竟结构就不一样。
楼上的，怎么不能比呀，KTP的非线形系数好，价格便宜呀
[B]以下是引用[I]alanick[/I]在2005-12-3 10:39:00的发言：[/B][BR]free兄，15W的绿光，用什么晶体比较好，最佳工作温度多少度，给点建议
楼上高手多，你们都是专业的，我连业余的都不是，只是爱好。
今天下午看了两个多小时的Sam's Laser FAQ，启发不少，看到其中的一段，不知是否与这个有关：
The required type and size of a the non-linear crystal depends on your application.
If you want to do frequency doubling (SHG - Second Harmonic Generation) of a CW or quasi-CW beam them a KTP crystal with a 3 x 3 mm aperture will suffice up to about 70 or 80 W of extracted green output power. If you are looking for higher powers use a 5 x 5 mm crystal and a respectively bigger beam waist. This will give you enough room for outputs of several hundreds of watts, and is the crystal size used in the current record holding laser for most green output power.
If you are thinking of using a SHG crystal for a pulsed laser, KDP would actually be your best bet. As a general rule of thumb with a electro-optically Q-switched laser, you want the spot size on your SHG no smaller than your output beam diameter. As it is extremely expensive to get a large KTP crystal, KDP is often used, and with high power pulsed lasers, the lower nonlinear coefficient is not noticed.
The damage threshold for a normal KTP crystal is 100 to 500 megawatts per square centimeter. The efficiency increases as the power density increases, so the power output at the second harmonic increases exponentially as the power density increases. However, although it is true that the damage threshold is very high in terms of power, it is much lower in terms of energy. Damage can occur at tens of joules per square cm. That's one reason why large doubled YAGs like the Laserscope systems can't be gated with the Q-switch driver. At high repetition rates, the first pulse supression goes isn't effective in those lasers, so the energy goes up in the first pulse eating the optics, normally starting with the KTP.
LBO has a much lower nonlinear coefficient for 1064 nm SHG than KTP. However, it also have a much higher damage threshold. LBO is normally only used in systems that either (1) use very high powers (i.e., 100 W class lasers) or (2) need one of the optical properties of the crystal, such as the small angular acceptance angle. Since LBO has a lower nonlinear coefficient, it requires the use of a much longer crystal.
alanick兄，我认为还是用LBO来得稳当，就选择非临界相位匹配，温度为148℃。
现在在那里高就啊？
[B]以下是引用[I]ydjkzbh[/I]在2005-12-18 21:56:00的发言：[/B][BR]KTP做到4瓦都是没有问题的,至少我就见过了.不知道你们用的LBO怎么样,我见到的LBO都不怎么样
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