Abstract: Disclosed herein is a system for an apodization mask composed of multi-walled carbon nanotubes (MWCNTs) for absorbing unwanted stray light. An apodization mask is a precise pattern or shape that is mathematically derived using light scattering measurement techniques to achieve optimal light absorption. Also disclosed herein is an apparatus for a duplex telescope with stray light suppressing capabilities comprising: a primary mirror for transmitting and receiving light; a secondary mirror for defocusing transmitted light onto the primary mirror and for focusing received light; a photodetector which receives light; a laser transmitter which transmits light; and an apodization mask for absorbing stray transmitted light.

Abstract: A method and system for stabilizing a laser to a frequency reference with an adjustable offset. The method locks a sideband signal generated by passing an incoming laser beam through the phase modulator to a frequency reference, and adjusts a carrier frequency relative to the locked sideband signal by changing a phase modulation frequency input to the phase modulator. The sideband signal can be a single sideband (SSB), dual sideband (DSB), or an electronic sideband (ESB) signal. Two separate electro-optic modulators can produce the DSB signal. The two electro-optic modulators can be a broadband modulator and a resonant modulator. With a DSB signal, the method can introduce two sinusoidal phase modulations at the phase modulator. With ESB signals, the method can further drive the optical phase modulator with an electrical signal with nominal frequency ?1 that is phase modulated at a frequency ?2.

Abstract: A method and system for stabilizing a laser to a frequency reference with an adjustable offset. The method locks a sideband signal generated by passing an incoming laser beam through the phase modulator to a frequency reference, and adjusts a carrier frequency relative to the locked sideband signal by changing a phase modulation frequency input to the phase modulator. The sideband signal can be a single sideband (SSB), dual sideband (DSB), or an electronic sideband (ESB) signal. Two separate electro-optic modulators can produce the DSB signal. The two electro-optic modulators can be a broadband modulator and a resonant modulator. With a DSB signal, the method can introduce two sinusoidal phase modulations at the phase modulator. With ESB signals, the method can further drive the optical phase modulator with an electrical signal with nominal frequency ?1 that is phase modulated at a frequency ?2.