A method and apparatus for determining the temperature of a substrate within a processing chamber are described herein. The methods and apparatus described herein utilize an etalon assembly and a heterodyning effect to determine a first temperature of a substrate. The first temperature of the substrate is determined without physically contacting the substrate. A separate temperature sensor also measures a second temperature of the substrate and/or the substrate support at a similar location. The first temperature and the second temperature are utilized to calibrate one of the temperature sensors disposed within the substrate support, a model of the processes performed within the processing chamber, or to adjust a process parameter of the process performed within the processing chamber.

The invention relates to a device and method for imaging electromagnetic radiation from an object. The device includes entrance optics for allowing the electromagnetic radiation to enter the device, including an image plane onto which an image of the object is to be imaged. The device includes an interferometer having a measurement arm, wherein the image plane is in the measurement arm. The device includes a transformation layer, at the image plane, for transforming the electromagnetic radiation into a spatiotemporal variation of the refractive index of the transformation layer for causing spatiotemporal optical phase differences in the measurement arm of the interferometer that are processed to result in a representative image of the object.

Hotspot monitoring system for superconducting devices including: —a superconductor; —a first optical waveguide attached to the superconductor for providing a first optical signal; —a second optical waveguide for providing a reference signal; and—interference means configured to overlay or superimpose the first optical signal and the reference optical signal to produce an optical interference signal.

Techniques and circuitry for a semiconductor laser with enhanced lasing wavelengths stabilization are described. A semiconductor laser can generate an optical signal (e.g., single or multi-wavelength), for use in a Dense Wavelength Division Multiplexing (DWDM) interconnect system. The stabilization circuitry can include temperature sensor circuitry that measures an operational temperature of the semiconductor laser, and a feedback controller that can determine a temperature-induced wavelength shift that may be experienced by the multi-wavelength optical signal based on the laser's temperature. The feedback controller is also configured to generate a compensation signal that is determined to cause a complimentary shift in the multi-wavelength optical signal, where the complimentary shift can compensate for the temperature-induced wavelength shift. An integrated MOS capacitor of the laser can be charged by the signal in a manner that effectuates the complimentary shift and tunes the multi-wavelength optical signal to compensate for temperature-induced shift, thereby enhancing stabilization.

A self-delayed homodyne interferometer includes light source unit, a splitting unit, an interference signal acquisition unit, a scattered light intensity acquisition unit, and a signal processing unit. The light source unit generates probe light. The splitting unit splits into two branches, Brillouin backscattered light occurring in an optical fiber to be measured with the probe light. The acquisition unit receives scattered light of one branch, and uses a self-delayed homodyne interferometer to generate an interference signal. The acquisition unit receives scattered light of the other branch, and acquires intensity of the scattered light. The signal processing unit separates and acquires a frequency shift amount from the intensity of the interference signal, and strain and temperature change from the intensity of the scattered light. The acquisition unit can change a phase of the scattered light of the one of the two branches.

A method of interferometric optical sensing via spatial demodulation includes emitting a laser beam; splitting the laser beam into a reference beam and an interrogation beam; converting a desired signal into a change in the optical path of the interrogation beam via an optical sensor; and capturing the reference beam and the interrogation beam via a camera, wherein the interrogation beam is incident to the camera at a first angle and the reference beam is incident to the camera at a second angle different from the first angle, thereby causing an interference pattern at the camera.

The present disclosure is directed to a fiber optic bolometer device. In an implementation, a fiber optic bolometer device includes an optical fiber and a silicon layer that comprises a Fabry-Prot interferometer. The silicon layer includes a first surface and a second surface. The fiber optic bolometer device includes a reflective dielectric film disposed over the first surface of the silicon layer where the reflective dielectric film is adjacent to an end face of the optical fiber. The fiber optic bolometer device also includes an absorptive coating disposed over the second surface of the silicon layer (e.g., the surface distal to the end face of the optical fiber).

A self-delayed homodyne interferometer includes light source unit, a splitting unit, an interference signal acquisition unit, a scattered light intensity acquisition unit, and a signal processing unit. The light source unit generates probe light. The splitting unit splits into two branches, Brillouin backscattered light occurring in an optical fiber to be measured with the probe light. The acquisition unit receives scattered light of one branch, and uses a self-delayed homodyne interferometer to generate an interference signal. The acquisition unit receives scattered light of the other branch, and acquires intensity of the scattered light. The signal processing unit separates and acquires a frequency shift amount from the intensity of the interference signal, and strain and temperature change from the intensity of the scattered light. The acquisition unit can change a phase of the scattered light of the one of the two branches.

A method and apparatus for determining the temperature of a substrate within a processing chamber are described herein. The methods and apparatus described herein utilize an etalon assembly and a heterodyning effect to determine a first temperature of a substrate. The first temperature of the substrate is determined without physically contacting the substrate. A separate temperature sensor also measures a second temperature of the substrate and/or the substrate support at a similar location. The first temperature and the second temperature are utilized to calibrate one of the temperature sensors disposed within the substrate support, a model of the processes performed within the processing chamber, or to adjust a process parameter of the process performed within the processing chamber.

A fiber optic sensor, a process for utilizing a fiber optic sensor, and a process for fabricating a fiber optic sensor are described, where a double-side-polished silicon pillar is attached to an optical fiber tip and forms a Fabry-Prot cavity. In an implementation, a fiber optic sensor in accordance with an exemplary embodiment includes an optical fiber configured to be coupled to a light source and a spectrometer; and a single silicon layer or multiple silicon layers disposed on an end face of the optical fiber, where each of the silicon layer(s) defines a Fabry-Prot interferometer, and where the sensor head reflects light from the light source to the spectrometer. In some implementations, the fiber optic sensor may include the light source coupled to the optical fiber; a spectrometer coupled to the optical fiber; and a controller coupled to the high speed spectrometer.