Andorra Optics President Jim McCann has authored or co-authored several technical papers covering optical system design, fabrication and testing and diffraction, listed below in chronological order. In all of these systems, Andorra Optics was involved in the design, prototype fabrication, testing, and production support demonstrating a commitment to the complete product development cycle.
The papers were published in SPIE Journal Proceedings. Papers are available as PDF files.
- Compact Multi-Band (VIS/IR) Zoom Imager for High-Resolution Long Range Surveillance; SPIE Proc., vol. 5783, 7/2005 (vis_ir.pdf)
- Membrane Mirror Light Modulator Technology; co-author with Cardinal Warde of Optron Systems; SPIE Proc., vol. 3951, 1/2000 (membrane.pdf)
Abstract: We have incorporated membrane mirror technology over a discrete array of pixel wells to create both high-efficiency optical shutters and spatial light modulators (SLM). A continuous metalized-membrane mirror with greater than 98% reflectivity minimizes optical insertion loss. This mirror is electrostatically deformed into the wells with either a common electrode (shutter) or pixilated electrodes (SLM). By using a spatial filter, analog intensity optical modulation is realized. Both 1-D (linear) and 2-D grating pixel patterns have been investigated. With the appropriate pixel dimensions, both coherent monochromatic and broadband incoherent light within the 0.25 to 10.6 micron range can be modulated with contrast ratios up to 1000:1. Small well sizes (approximately 10-micron diameter) allow for modulation speeds up to 1 MHz.
The theoretical foundations for the well layout, the membrane mirror deformation and its diffraction properties, and the design trade-offs are detailed. We have applied our membrane mirror technology to CMOS VLSI circuits creating a high-speed, high efficiency spatial light modulator capable of 80x64 resolution and scalable to HDTV standards. The membrane mirror SLM provides either amplitude or phase modulation. In the phase modulation mode, at least two waves of stroke per discrete well are possible.
- The Design, Fabrication, and Application of Diamond Turned Null Lenses for Testing Generalized Aspheric Surfaces; SPIE Proc., vol. 1531, 7/91 (surface.pdf)
Abstract: This paper describes the optical design, fabrication and use of single element null lenses for the interferometric testing of generalized aspheric surfaces. The aspheric singlet is designed to work in collimated light, without a field lens, and allows for measurement of surface figure error over the entire clear aperture. The null lens is a single element of multi-spectral zinc sulfide (ZnS). This material is durable, easily diamond machined and provides good transmission at the test wavelength of 0.6328 microns. All reference surfaces needed for alignment are diamond machined into simple collars that hold the null lens and surface under test. This allows easy and accurate optical alignment and minimizes setup time.
- Analysis and Performance Limits of Diamond Turned Diffractive Lenses for the 3-5 and 8-12 Micrometers Regions; co-author with Max Riedl of OFC; SPIE Proc., vol. CR 38, 4/91 (analysis.pdf)
Abstract: Diffractive optical imaging elements have been proposed in numerous papers over the past decade. Few have been produced in quantities. The primary method of fabricating such diffractive elements has been reactive ion etching of a multi-level surface relief grating on one side of a lens. This approximation is known as Binary Optics. Recent experiments have shown that single point diamond turning can be very effective in generating continuous diffraction phase profiles. Combined with the long established method of aspherizing, this machining process is especially suitable for applications in the infrared spectrum. It provides a means of reducing the number of lens elements otherwise required for an objective to correct existing aberrations.
- Diamond Turned Null Reflectors for Generalized Aspheric Metrology; SPIE Proc., vol. 1132, 7/90 (diamond.pdf)
Abstract: This paper addresses the problem of testing generalized aspheric surfaces. The technique involves the use of diamond machined null reflective compensators. These null mirrors can be designed, fabricated and qualified in-house quickly which is a big advantage in a production environment. Methods of null reflector design as well as test configuration alignment will be discussed. Several examples of this method will be used to illustrate the technique.
- Telescope Designs for Precision Astrometry; SPIE Proc., vol. 818, 7/87 (telescope.pdf)
Abstract: In this paper a design study is described for telescopes to be used in precision astrometry. Specifically, the application is the search for planets outside the solar system. The design is complex because of the need to be spectrally independent, have low distortion, and be free of coma and other asymmetric aberration. The image requirements for astrometry are defined along with two-mirror telescope designs for the application. Effects of misalignment and long term stability are considered.