Optical spectrum analyzer and optical spectrum detecting method
AssigneeFujitsu Limited
InventorTakeo Iwama
Life of this patent
Estimating the term…
Abstract
In an optical spectrum analyzer comprising a spectrograph and a photodevice array, and an optical spectrum detecting method, a wavelength deviation, from an assigned wavelength, of a light detected by a photodevice array which detects a wavelength of a diffraction light or a non-diffraction light from an acoustooptic device, is detected and a feedback control to a diffraction angle of the acoustooptic device is performed. Also, without using a feedback control, an exit light and a diffraction light from the acoustooptic device are respectively received by two photodevice arrays and the photodevices are arranged in order to mutually compensate gaps between the photodevices, whereby a center of each photodevice is similarly made coincide with a peak of an optical beam to be received.
Claims22
An optical spectrum analyzer comprising:
- a spectrograph outputting light,
- an acoustooptic device diffracting the light output from the spectrograph at a diffraction angle, the acoustooptic device being controllable to control the diffraction angle,
- a photodevice array detecting light in a diffracted or non-diffracted state from the acoustooptic device, and
- a control circuit detecting a wavelength deviation, between an assigned wavelength, and a wavelength of the light detected by the photodevice array and controlling the acoustooptic device to control the diffraction angle in accordance with the detected wavelength deviation.
An optical spectrum analyzer comprising:
- a spectrograph outputting light,
- an acoustooptic device diffracting the light output from the spectrograph,
- a first photodevice array comprising photodevices with gaps between the photodevices, and
- a second photodevice array comprising photodevices, the photodevices of the second photodevice array being arranged to compensate for the gaps between the photodevices of the first photodevice array, the first and second photodevice arrays together detecting the light in a diffracted and non-diffracted state from the acoustooptic device.
A method comprising:
- detecting, when an output light of a spectrograph is diffracted by an acoustooptic device in accordance with a controllable diffraction angle of the acoustooptic device and the light in a diffracted or non-diffracted state from the acoustooptic device is detected by a photodevice array, a wavelength deviation, between an assigned wavelength and a wavelength of the light detected by the photodevice array, and
- controlling the diffraction angle of the acoustooptic device in accordance with the detected wavelength deviation.
An optical spectrum analyzer comprising:
- an acoustooptic device diffracting light at a diffraction angle, the optical spectrum analyzer detecting a spectrum in accordance with the diffracted light, wherein the acoustooptic device is controllable to control the diffraction angle and thereby improve measurement accuracy of the detected spectrum.
An optical spectrum analyzer comprising:
- an acoustooptic device diffracting light at a diffraction angle, the optical spectrum analyzer detecting a spectrum in accordance with the diffracted light;
- and
- means for controlling the acoustooptic device to control the diffraction angle and thereby improve measurement accuracy of the detected spectrum.
An optical spectrum analyzer comprising:
- an acoustooptic device diffracting light in accordance with a diffraction angle, the acoustooptic device being controllable to control the diffraction angle;
- and
- a photodevice array receiving the diffracted light, the acoustooptic device being controlled in accordance with the diffracted light as received by the photodevice array to control the diffraction angle.
An optical spectrum analyzer comprising:
- an acoustooptic device diffracting light in accordance with a diffraction angle;
- a photodevice array receiving the diffracted light;
- and
- means for controlling the acoustooptic device to control the diffraction angle to thereby improve measurement accuracy of the optical spectrum analyzer.
An optical spectrum analyzer comprising:
- a spectrograph outputting light;
- an acoustooptic device diffracting the light output from the spectrograph at a diffraction angle;
- a photodevice array detecting light in a diffracted or non-diffracted state from the acoustooptic device;
- and
- means for detecting a wavelength deviation between an assigned wavelength and a wavelength of the light detected by the photodevice array, and for controlling the acoustooptic device to control the diffraction angle in accordance with the detected wavelength deviation.
An optical spectrum analyzer comprising:
- an acoustooptic device diffracting light;
- a first photodevice array comprising photodevices with gaps between the photodevices;
- and
- a second photodevice array comprising photodevices, the photodevices of the second photodevice array being arranged to compensate for the gaps between the photodevices of the first photodevice array, the first and second photodevice arrays together detecting light in a diffracted and non-diffracted state from the acoustooptic device to thereby detect a spectrum by the optical spectrum analyzer.
Dependencies are inferred from the claim text.