PROTOTYPES AND MODULATION FUNCTIONS OF CLASSICAL AND NOVEL CONFIGURATIONS OF OPTICAL CHOPPER WHEELS

Optical choppers with rotating wheels are some of the most used macroscopic optomechatronic devices for the controlled modulation, attenuation or obscuration of light in a wide area of applications. We discuss and compare the modulation functions produced by two types of chopper wheels: the classical device, with windows with linear edges, and the eclipse chopper (with windows with circular edges) that, to the best of our knowledge, we have introduced. This discussion is based on the analysis and the design we have previously developed for these various devices, for top-hat (constant over the entire section) light beam distributions. While the comparison of the different shapes of transmitted signals allows for the proper choice of the most appropriate device and parameters to obtain the modulation function that is fit for a certain application, the present work also presents the mechanical setup we have designed and manufactured for testing choppers with rotating wheels. A series of prototype wheels with different, optimized profiles were obtained for the purpose. The simulation and the electro-erosion programs for the wire electro-erosion of aluminum plates to manufacture the wheels are presented. An advantageous double wheel solution has been developed to obtain wheels with windows of different shapes and sizes, and the testing of this final assembly concludes the study.

[1]  Richard B Rosen,et al.  Sequential optical coherence tomography and confocal imaging. , 2004, Optics letters.

[2]  Virgil-Florin Duma.  Optical choppers with circular-shaped windows: Modulation functions , 2011 .

[3]  Z. Yamani,et al.  Highly sensitive electronically modulated photoacoustic spectrometer for ozone detection. , 2007, Applied optics.

[4]  Michael Bass,et al.  Handbook of optics , 1995 .

[5]  B A Soltz,et al.  Two-color mid-infrared thermometer with a hollow glass optical fiber. , 1997, Applied optics.

[6]  Virgil-Florin Duma.  Theoretical approach on optical choppers for top-hat light beam distributions , 2008 .

[7]  R. Scheps,et al.  Performance of a diode-pumped laser repetitively Q-switched with a mechanical shutter. , 1994, Applied optics.

[8]  L. Milano,et al.  Detection of x rays with a fiber-optic interferometric sensor. , 1993, Applied optics.

[9]  Justin Pedro,et al.  Combined confocal/en face T-scan-based ultrahigh-resolution optical coherence tomography in vivo retinal imaging. , 2006, Optics letters.

[10]  Virgil-Florin Duma.  Radiometric versus geometric, linear, and nonlinear vignetting coefficient. , 2009, Applied optics.

[11]  Guenter Hofmann,et al.  Influence of nonideal chopper design on nonuniformity in uncooled pyroelectric staring array systems , 1995, Optics & Photonics.

[12]  Dennis K. Killinger,et al.  Transient fluorescence spectroscopy of terbium doped dipicolinic acid: a fluorescence lifetime measurement technique , 2009 .

[13]  M Ueda,et al.  High-efficiency diffractive micromachined chopper for infrared wavelength and its application to a pyroelectric infrared sensor. , 1998, Applied optics.

[14]  Alistair Armitage,et al.  Harmonic errors associated with the use of choppers in optical experiments , 2006 .

[15]  D. Haner,et al.  Redesign and improved performance of the tropospheric ozone lidar at the Jet Propulsion Laboratory Table Mountain Facility. , 2002, Applied optics.

[16]  Richard M. White,et al.  Microfabricated optical chopper , 1994 .

[17]  T E Furtak.  Sinusoidal radiation chopper for modulation of the maximum available ight intensity. , 1977, Applied optics.

[18]  Lijiang Zeng,et al.  Two-dimensional surface profile imaging technique based on a double-grating frequency shifter. , 2005, Applied optics.

[19]  Hermann Bittner,et al.  Optical system of the SOFIA Telescope , 1998, Astronomical Telescopes and Instrumentation.

[20]  Virgil-Florin Duma,et al.  Optical choppers: modulators and attenuators , 2010, ROMOPTO International Conference on Micro- to Nano- Photonics.

[21]  D P Butler,et al.  Two-color thermal detector with thermal chopping for infrared focal-plane arrays. , 2001, Applied optics.

[22]  Hannu Olkkonen.  Chopper stabilized laser-Doppler skin blood velocimeter , 1993, Other Conferences.

[23]  R M Benmair,et al.  Solar-pumped Er,Tm,Ho:YAG laser. , 1990, Optics letters.

[24]  Xia Wang,et al.  Modulate chopper technique used in pyroelectric uncooled focal plane array thermal imager , 2002, SPIE/COS Photonics Asia.

[25]  Virgil-Florin Duma,et al.  Neutral density filters with Risley prisms: analysis and design. , 2009, Applied optics.

[26]  J L Bufton,et al.  Fourier spectrum of a chopped bivariate normal intensity distribution. , 1970, Applied optics.

[27]  D Vincent.  Amplitude modulation with a mechanical chopper. , 1986, Applied optics.