Tags: deformable mirror, adaptive optics, boston micromachines, retinal imaging, free-space communication, modulating retroreflector, segmented, laser beam, SLM, spatial light modulator, deep tissue microscopy, SPIE, BMC, imaging systems, Photonics West, microscopy, two photon, optical chopper, optical modulator, chopper, Adaptive Optics Scanning Laser Ohphthalmoscope, Joslin Diabetes Center, Mirrors
Just a few weeks ago we arrived back from the Photonics West 2014 exhibition and conference in San Francisco, CA. I wanted to share details and further observations on the show for those present at the show and those not being able to attend this year.
For the first time we made the decision to also attend the BiOS exhibition for the few days prior to PWest. Not being quite sure what to expect for booth traffic, especially since it conflicted with the superbowl, we still generated a good amount of interest for the smaller show. Our main presentations focused on our new adaptive optics-enhanced scanning laser ophthamoscope (AOSLO), the Apaeros Retinal Imaging System, which includes our Multi-DM, and the Superpenetration Multiphoton Microscopy technique, which is enabled by our Kilo-SLM and high speed S-Driver. Although both exhibits generated respectable notice and positive feedback, most people were familiar with the Superpentration Multiphoton work being done. Either wanting to try two-photon microscopy themselves or already in the process of doing so, our Kilo-SLM paired with our high speed S-driver presented data that was intriguing to most.
After wrapping up BiOS, we headed to the opposite side of the South hall at the Moscone Center for a larger booth setup for PWest. Here we had our entire mirror family on display, as well as live demonstrations of the Reflective Optical Chopper and Wavefront Sensorless Adaptive Optics Demonstrator for Beam Shaping (WSAOD-B). For this part of the exhibition, I would say our deformable mirrors produced the most attention, most likely due to our wide assortment of shapes and actuator counts up to 4092. The WSAOD-B live demonstration did generate a great deal of attention, as most people are unaware of how sensorless AO works. Besides our deformable mirror line, I would still say the Multiphoton Microscopy overview was initiating even further interest here as well.
Overall BMC had a great show and it seemed well worth it to expand our exhibit onto BiOS beforehand. Although this was my first time attending the show, I noticed every inch of space at PWest being used for exhibitor tables and booths, even setting up in front of the bathrooms! I hope to see PWest advance even larger, maybe one day expanding to its third space, West Hall. I look forward to next year’s show and hope to reconnect with you all again throughout the year.
If you were not able to attend the show and would like any information on the products mentioned, please visit our website and download our whitepapers.
Boston Micromachines has been awarded US$ 1.2M in contracts by NASA's Small Business Innovation Research Program (SBIR) to support space-based astronomy research. Now, one might wonder, considering this is astronomy, “why is anyone spending any money to develop deformable mirrors for use in space telescopes looking out at the stars? I thought that deformable mirrors were used to remove aberrations introduced by the atmosphere. There’s no atmosphere up there!”
Well, you’d be right: There is no atmosphere up there. But, there are aberrations: In the optical system. When systems are designed, none of them are completely perfectly aligned. There’s no such thing. But, when you’re looking for planets around stars in other galaxies, you need things to be well aligned. VERY well aligned. So, to compensate for any misalignments introduced either during transit to space or thermal variations in the instrument, you can use a deformable mirror as part of an adaptive optics system. So, for this, we are designing a 1021 segment (3063 actuator), tip-tilt-piston deformable mirror. It is the largest ever designed of this type and is expected to be used as part of a coronagraph telescope for exo-planet research.
Two other things to worry about are power and weight. In satellites, there is a very limited amount of power, and the weight greatly affects the cost to put the satellite into orbit. In terms of the mirror, MEMS has that taken care of: The power is extremely low and the weight is many orders of magnitude lower than traditional piezo-electric-based mirrors. So, the other half of the equation is the drive electronics. As part of this research, BMC is designing multiplexed drive electronics which will reduce the size and weight significantly and lower the power even further.
You put the two parts together, mirror hardware and drive electronics, and you have a low-cost, low-power, lightweight solution for the most cutting edge astronomy research going on right now.
If you have any questions, please contact me directly: I would be happy to talk about these products or refer you to the folks who are attacking this challenging problem.
Link to press release.
(Image credit: A giant Hubble mosaic of the Crab Nebula, a supernova remnant)
Although William Wallace shouted this in the movie, “Braveheart,” as he died in the hopes to inspire others to join his fight against tyranny, our interest here at Boston Micromachines is related to “degrees of freedom” rather than individual rights. I chose this as a post because numerous times we have come across customers who miscalculate the minimum number of control points (re: actuators) needed to satisfy their wavefront control needs because the forget about this simple concept. Here’s an example:
A customer recently came to us insisting that they needed one of our advanced tip-tilt-piston devices over a continuous surface deformable mirror. Their reasoning was that with the same number of actuators, to correct for their wavefront, tipping and tilting the individual segments would give them more control than using the simple piston mechanism of our continuous device. This is true if you compare the number of segments (with three actuators) to the number of single actuators of a continuous DM. However, if you choose to use a tip-tilt-piston device over a continuous surface mirror, you actually need more actuators (if you work out the numbers, 1.8 times more) to achieve the same level of correction capability. This has been explained and presented very well by Claire Max at UC Santa Cruz. See the presentation materials here (Slide 47 goes over the equations).
If we step back from the equations and look for the basic concept behind this, it boils down to the ability to change the profile of the surface in many more ways using a continuous membrane as opposed to stiff, separate segments. Even more simply put: If you want to approximate a curvy line using only a few points (five, let’s say), would you prefer to use a slightly less curvy line, or a series of straight lines?
The figure below illustrates this concept.
So, the next time you’re considering wavefront control, keep this in mind before hitching your wagon to a particular architecture. THINK FREEDOM!!!!!