Thermal Balance and Active Damping of a Piezoelectric Deformable Mirror for Adaptive Optics

Piezoelectric unimorph deformable mirrors offer a cheap solution to adaptive optics, with mass production capability. However, standard solutions have significant drawbacks: (i) the static shape is sensitive to the temperature, and (ii) the low structural damping limits the control bandwidth, because of the interaction between the shape control and the vibration modes of the mirror. This paper discusses how these two problems may be alleviated by using a mirror covered with an array of actuators working in d31 mode on the back side and a ring of transducers (actuators and sensors) on the front side, outside the pupil of the mirror.

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Shape control study of MEMS deformable mirror for adaptive optics in Indus-2 using piezo response function based TLBO algorithm

10.1063/5.0017408 ◽

2020 ◽

Author(s):

Vikas Saroha ◽

Sumit ◽

Rahul Shukla ◽

A. K. Srivastava ◽

R. K. Sahu

Keyword(s):

Adaptive Optics ◽

Response Function ◽

Shape Control ◽

Deformable Mirror ◽

Tlbo Algorithm ◽

Control Study

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Active shape control of a deformable mirror in an adaptive optics system

1997 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, PACRIM. 10 Years Networking the Pacific Rim, 1987-1997 ◽

10.1109/pacrim.1997.620330 ◽

2002 ◽

Author(s):

A. Chellabi ◽

Y. Stepanenko ◽

S. Dost

Keyword(s):

Adaptive Optics ◽

Shape Control ◽

Deformable Mirror ◽

Active Shape ◽

Adaptive Optics System

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Off-axis point spread function reconstruction from a dual deformable mirror adaptive optics system

10.1117/12.790026 ◽

2008 ◽

Cited By ~ 1

Author(s):

O. Keskin ◽

R. Conan ◽

C. Bradley ◽

C. Blain

Keyword(s):

Adaptive Optics ◽

Point Spread Function ◽

Deformable Mirror ◽

Point Spread ◽

Spread Function ◽

Adaptive Optics System ◽

Function Reconstruction

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A New Design of Large Stroke Micro-Deformable Mirror Actuated by Electrostatic Repulsive Force

2008 Second International Conference on Integration and Commercialization of Micro and Nanosystems ◽

10.1115/micronano2008-70058 ◽

2008 ◽

Cited By ~ 1

Author(s):

Fangrong Hu ◽

Jun Yao ◽

Chuankai Qiu ◽

Dajia Wang

Keyword(s):

Electric Field ◽

Resonant Frequency ◽

Adaptive Optics ◽

Bottom Electrode ◽

Sacrificial Layer ◽

Electrostatic Force ◽

Repulsive Force ◽

Deformable Mirror ◽

Optical Aberrations ◽

Out Of Plane

In this paper, a MEMS mirror actuated by an electrostatic repulsive force has been proposed and analyzed. The mirror consists of four U-shape springs, a fixed bottom electrode and a movable top electrode, there are many comb fingers on the edges of both electrodes. When the voltage is applied to the top and bottom electrodes, an asymmetric electric field is generated to the top movable fingers and springs, thus a net electrostatic force is produced to move the top plate out of plane. This designed micro-mirror is different from conventional MDM based on electrostatic-attractive-force, which is restricted by one-third thickness of the sacrificial layer for the pull-in phenomenon. The characteristic of this MDM has been analyzed, the result shows that the resonant frequency of the first mode is 8 kHz, and the stroke reaches 10μm at 200V, a MDM with large strokes can be realized for the application of adaptive optics in optical aberrations correction.

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Frequency Bandwidth Adjustment by Precision Post-Processing for a 0.78–0.95 THz Band SIS Mixer

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.643.157 ◽

2015 ◽

Vol 643 ◽

pp. 157-163

Author(s):

Akihira Miyachi ◽

Takafumi Kojima ◽

Yasunori Fujii ◽

Masanori Takeda ◽

Yoshinori Uzawa ◽

...

Keyword(s):

Mass Production ◽

Noise Temperature ◽

Back Side ◽

Frequency Bandwidth ◽

Post Processing ◽

Sis Mixer ◽

Optimal Method ◽

High Frequencies ◽

Em Simulation ◽

The Relationship

In this study, we demonstrate a method for adjusting the frequency bandwidth of a Superconductor-insulator-superconductor (SIS) mixer device by controlling its thickness after microfabrication. We estimate the relationship between SIS mixer device thickness and frequency bandwidth using electromagnetic (EM) simulation. We propose an optimal method for the precision polishing of the back side of the device. We evaluate the noise temperature and measure the frequency bandwidth of SIS mixer devices with different thicknesses. This study presents the adjustment of the frequency bandwidth of a device through controlling its thickness after microfabrication. This technique may improve the yield of SIS mixer device mass production and support the construction of receivers for ultra-high frequencies such as Atacama Large Millimeter/Submillimeter Array (ALMA) Band 10.

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