Rainbow Heterodyne Detection

	Rainbow Heterodyne Detection The objective of synthetic array heterodyne detection is to isolate regions of a large area detector surface into virtual pixels. This provides the benefits of having multiple pixels (for example, to make an image) without having to have physical pixels (i.e. isolated detector elements). The detector can be a simple single wire output over which all the virtual pixels can be read out continuously and in parallel. The pixels are multiplexed in the frequency domain. This solves two common problems encountered in optical heterodyne detection. First, heterodyne signals are beat frequencies between the signal source and a reference source (dubbed local oscillator). They are not DC light levels but oscillating signals and thus unlike conventional detectors the light flux from the signal cannot be integrated on a capacitor. Therefore, to have an array of pixels, each pixel must be backed by AC amplifier and detection circuit which is complex. With synthetic array detection, all th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Synthetic Array Heterodyne Detection Optical heterodyne detection is a method of extracting information encoded as modulation of the phase, frequency or both of electromagnetic radiation in the wavelength band of visible or infrared light. The light signal is compared with standard or reference light from a "local oscillator" (LO) that would have a fixed offset in frequency and phase from the signal if the latter carried null information. "Heterodyne" signifies more than one frequency, in contrast to the single frequency employed in homodyne detection. The comparison of the two light signals is typically accomplished by combining them in a photodiode detector, which has a response that is linear in energy, and hence quadratic in amplitude of electromagnetic field. Typically, the two light frequencies are similar enough that their difference or beat frequency produced by the detector is in the radio or microwave band that can be conveniently processed by electronic means. This technique became widely applicable to top ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Optical Heterodyne Detection Optical heterodyne detection is a method of extracting information encoded as modulation of the phase, frequency or both of electromagnetic radiation in the wavelength band of visible or infrared light. The light signal is compared with standard or reference light from a "local oscillator" (LO) that would have a fixed offset in frequency and phase from the signal if the latter carried null information. "Heterodyne" signifies more than one frequency, in contrast to the single frequency employed in homodyne detection. The comparison of the two light signals is typically accomplished by combining them in a photodiode detector, which has a response that is linear in energy, and hence quadratic in amplitude of electromagnetic field. Typically, the two light frequencies are similar enough that their difference or beat frequency produced by the detector is in the radio or microwave band that can be conveniently processed by electronic means. This technique became widely applicable to top ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Local Oscillator In electronics, a local oscillator (LO) is an electronic oscillator used with a mixer to change the frequency of a signal. This frequency conversion process, also called heterodyning, produces the sum and difference frequencies from the frequency of the local oscillator and frequency of the input signal. Processing a signal at a fixed frequency gives a radio receiver improved performance. In many receivers, the function of local oscillator and mixer is combined in one stage called a " converter" - this reduces the space, cost, and power consumption by combining both functions into one active device. Applications Local oscillators are used in the superheterodyne receiver, the most common type of radio receiver circuit. They are also used in many other communications circuits such as modems, cable television set top boxes, frequency division multiplexing systems used in telephone trunklines, microwave relay systems, telemetry systems, atomic clocks, radio telescopes, and milita ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Acousto-optic Deflector An acousto-optic deflector (AOD) spatially controls the optical beam. In the operation of an acousto-optic deflector the power driving the acoustic transducer is kept on, at a constant level, while the acoustic frequency is varied to deflect the beam to different angular positions. The acousto-optic deflector makes use of the acoustic frequency dependent diffraction angle, where a change in the angle \Delta \theta_d as a function of the change in frequency \Delta f given as, : (12) \ \Delta \theta_d = \frac\Delta f where \lambda is the optical wavelength and \nu is the velocity of the acoustic wave. AOM technology has made practical the Bose–Einstein condensation for which the 2001 Nobel Prize in Physics was awarded to Eric A. Cornell, Wolfgang Ketterle and Carl E. Wieman. Another application of acoustic-optical deflection is optical trapping of small molecules. AODs are essentially the same as acousto-optic modulators (AOMs). In both an AOM and an AOD, the amplitude and fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Optoelectronics Optoelectronics (or optronics) is the study and application of electronic devices and systems that find, detect and control light, usually considered a sub-field of photonics. In this context, ''light'' often includes invisible forms of radiation such as gamma rays, X-rays, ultraviolet and infrared, in addition to visible light. Optoelectronic devices are electrical-to-optical or optical-to-electrical transducers, or instruments that use such devices in their operation. ''Electro-optics'' is often erroneously used as a synonym, but is a wider branch of physics that concerns all interactions between light and electric fields, whether or not they form part of an electronic device. Optoelectronics is based on the quantum mechanical effects of light on electronic materials, especially semiconductors, sometimes in the presence of electric fields. * Photoelectric or photovoltaic effect, used in: photodiodes (including solar cells) phototransistors photomultipliers optois ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]