About half of our customers use our deformable mirrors for laser applications, such as beam shaping or steering. We get a lot of questions pertaining to laser power and handling for both our deformable mirrors and modulators. Below is a summary of the guidelines we use when discussing our technolgy.
The most important specification to note immediately if you are working with lasers is the damage threshold of our DM's. There are two mechanisms of failure to consider: mirror damage due to heating and coating delamination. The first failure mode is largely governed by the average power experienced by the DM. The rule of thumb that we follow is maximum average power of 20W/cm². For the second failure mode, the peak energy is of greatest concern. In this case, the threshold that we use is that of a standard thin-film gold metallic coating, in this case, 0.4J/cm². Depending on the DM system, the calculations may be slightly different. In order to ensure a DM is suitable for your application, we typically need to know as many of the following properties as possible: the pulse width of the laser, peak power, frequency, wavelength and beam size. This last pameter will help to determine which aperture size is required and if you need to change your beam size at all. Additional information on laser power can be found on our previous blog here.
From a power threshold standpoint, our modulator technology works similarly to our deformable mirror technology. However, it may have a slightly lower damage threshold due to the fact that the exposed surface is a thin layer of silicon nitride as opposed to the thicker polysilicon surface used for our deformable mirrors. Honestly, we do not have much experience testing the devices. If you are interested in carrying out testing, we would be glad to lend you some modulators to test.
If you are interested in learning more about customers' experience with high-power lasers used on our DM's, please click here to read Andrew Norton's paper on laser test performed using our DMs. Also, please visit our website or contact us for questions or additional information on how to obtain a device for testing.