Rockwell International Corporation

Teledyne Licensing, LLC

The Boeing Company

Teledyne Scientific and Imaging, LLC

Randolph L Hall

William H Southwell

Mohsen Khoshnevisan

Ray Carlisle Delcher

William J Gunning, Iii

Mark D Ewbank

William R Christian

Walter E Johnson

Frank J Woodberry

Rand D Dannenberg

Christopher D Johnson

Arthur Chiou

A laser beam steering apparatus includes a beam steering cell with an adjustable shape, with the cell having opposing Fabry-Perot filters, and a steering mechanism coupled to the cell to adjust its shape so that the direction of a laser beam emitted from the cell is changed in response to a change in the cell shape.

Large-angle agile laser beam steering apparatus and method

The disclosure relates to a method and apparatus for providing switching optical filter. The switching optical filter provides several functionalities at the same time. For example, the filter can be used to remove photons of undesirable wavelength, such as ultraviolet or infrared, while simultaneously switching from and between one mode to another in order to accommodate changing ambient light conditions. In one embodiment, the disclosure relates to a method for forming an optical filter, the method comprising: forming a first electrode layer on a substrate; forming an ion conductor layer to at least partially cover the first electrode layer; forming an optically transparent layer over the ion conductor layer, the optically transparent layer preventing transmission of photons having a first wavelength while transmitting photons of a second wavelength; and forming a second electrode layer to at least partially cover the optically transparent layer.

Method and apparatus for switching optical filters

An optical system employs an optical coating on a substrate positioned relative to an optical collection system. The thickness of the coating is tailored such that light perceived by the collection system over prescribed angles of acceptance has a spectral content that is unchanged, or changed in a prescribed manner, from that entering the system when the sensor is oriented in the 'look ahead' direction. The thickness of the coating is varied so that the wavelengths transmitted or reflected correspond to those required by a specific application. The invention is adaptable to system requirements that are centered about a single wavelength, or that require multiple wavelengths. The optical coating can take any of a number of forms, including stacked dielectric layers and rugate filters.

Optical coating and configuration for tailored spectral characteristics over viewing angle

A complementary comb filter pair, and method for making same, are described, wherein each comb filter element of the complementary pair can be fabricated during the same deposition run. The complementary comb filter is masked so as to retard the thin film growth of the coating, for example, a dielectric material, so as to produce a desired wavelength transmission profile.

Method for the design and fabrication of complementary optical comb filter pairs

A polarizing beamsplitter includes a gradient index film, such as a rugate filter, embedded in an optical medium. The rugate filter is comprises a thin film having a sinusoidal variation in refractive index through its thickness. The embedding medium may include a pair of prisms with the rugate filter between joining faces of the prisms. The rugate filter is embedded so that an incident beam in the embedding medium forms an angle with respect to a normal from the plane of the rugate filter. Embedded at a non-orthogonal angle, the rugate filter is highly transmissive for both the p- and s-polarized broadband components of the incident beam. The beamsplitter is highly reflective, however, at an s-polarization narrow wavelength reflection band determined by the refractive index variations of the rugate filter. Polarizing beamsplitters may be fabricated with multiple reflection bands, including reflection bands in spectral regions other than the visible spectrum. The polarizing beamsplitter can function as a polarizer, a beamsplitter, or a polarizing beamsplitter. An advantage of the invention is efficient reflection of s-polarized light at specific narrow wavelengths with high transmission of s-polarizations at all other wavelengths and p-polarizations at all wavelengths.

Narrow wavelength polarizing beamsplitter

A method is provided for monitoring and controlling the deposition of multiple layer thin films using a broadband spectral monitor and a generalized model of the film. A design specification, including the number of layers and the material, refractive index, and thickness of each layer, is provided for the desired thin film. A target optical thickness is computed for the end point of each layer using correction factors based on the generalized model, preferably a single layer model, of the multilayer thin film. A monitor chip, such as a silicon substrate, is used for monitoring the multiple layers of film deposition. During deposition of the film, a broadband spectral monitor (BBSM) comprising a source of broadband light is directed onto the monitoring chip. Light reflected by the monitoring chip is received by a photosensor that provides a broadband reflectance spectrum to a computer. The BBSM reflectance spectrum is fit to the generalized model to produce an output corresponding to the optical thickness of the deposited film. When the broadband spectral monitor optical thickness measurement equals the target optical thickness at the end point of the layer, deposition of that layer is terminated and deposition of the next layer may commence. This process is repeated during the deposition of each successive layer until the entire multiple layer thin film is complete.

Deposition of multiple layer thin films using a broadband spectral

A thin film, light absorbing coating comprises an analog structure fabricated by the simultaneous codeposition of absorbing and non-absorbing material. The two materials may comprise a non-absorbing dielectric material, such as silicon monoxide, and a metal, such as chromium, that is absorbing over the desired wavelength range. Individual evaporation rates for the two materials are adjusted during the codeposition process to achieve a continuously graded quintic transition between the absorbing material and the non-absorbing material. The continuous grading of the composition allows good light absorption properties to be maintained over a wide range of wavelengths. The total design thickness of the absorbing coating is on the order of a full wavelength of light. All wavelengths of incident light shorter than the design wavelength are absorbed into the coating. The coating is useful as a broad band light absorbing layer between a substrate and a spectrally selective reflective surface layer.

Broad band light absorbing film

An optical reflector includes a substrate, an absorbing layer deposited on the substrate for absorbing light within a broad range of wavelengths, and a rugate film deposited on the absorbing layer and adapted to reflect wavelengths of light within a predetermined range. The reflector may further include a buffer layer disposed between the substrate and the absorbing layer for promoting the adhesion of the absorbing layer to the substrate.

Rugate reflector

A method is provided for monitoring and controlling the deposition of an optical thin film having a refractive index gradient. The optical material to be deposited is evaporated at a controllable rate. In a coevaporation process, evaporation of material having a lower index of refraction is generally held at a predetermined rate while evaporation of material having a higher index of refraction is controllable. During deposition, the film and substrate are illuminated by a broadband light source. The incident light reflected by the film and substrate produces an interference pattern comprising a reflectance spectrum that is detected to compute an optical thickness estimate of the film. The detected reflectance is compared to a reflectance specified for that optical thickness by a predetermined refractive index profile of the desired film. The controllable rate of evaporation is then adjusted so that the refractive index of the material being deposited conforms to the predetermined profile.

Method of fabricating gradient index optical films

The thickness of growing thin film layer is monitored by directing a beam of circularly polarized monochromatic monitoring light into the layer and detecting the portion of the monitoring light reflected from the layer. The difference in phase between the s and p polarized components of the reflected light is measured and those thicknesses of the layer at which the difference in phase between the s and p components is zero are related to thicknesses which are an integral multiple of one fourth of the wavelength of the monitoring light in the layer. An apparatus for monitoring the thickness of a growing layer during the fabrication of an optical thin film includes a source of light for directing a beam of light at the growing layer and a polarizer between the source and the layer for converting the light beam to a linearly polarized beam. A quarterwave plate between the polarizer and the layer converts the linearly polarized beam to a circularly polarized beam, while a polarizing beam splitter receives the portion of the beam reflected from the layer and divides the portion into a +45.degree. polarized component and a -45.degree. polarized component. A first detector detects the intensity of the +45.degree. polarized component and a second detector detects the intensity of the -45.degree. polarized component.

Phase sensitive optical monitor for thin film deposition

A gradient index filter can be fabricated with integral antireflection properties without degrading the inband performance of the filter. The filter is for placement between an incident medium and a substrate to reflect incident electromagnetic energy having wavelengths within a predetermined band of wavelengths and to transmit incident electromagnetic energy having wavelengths outside of the reflection band. The filter includes an antireflecting portion having a nominal refractive index profile selected to reflect a minimum amount of electromagnetic energy from a theoretical interface between a first medium having a first predetermined refractive index and a second medium having a second predetermined refractive index. A band rejecting portion has a periodic refractive index profile whose periodicity and amplitude are selected to reflect a maximum amount of electromagnetic energy within the relfection band. At least part of the nominal refractive index profile is modulated by the superposition thereon of at least part of the periodic refractive index profile. The entire periodic refractive index profile maybe superimposed on the monial refractive index profile, while the periodic refractive index profile may be a rugate profile. In addition, the nominal incident and substrate refractive index profiles may be quintic refractive index profiles.

Spectral filter with integral antireflection coating

A method of fabricating an optical coating includes a layer pair, with a layer of a first optical material having a first refractive index and a first nominal thickness and a layer of a second optical material having a second refractive index and a second nominal thickness. The first layer is deposited, then its actual thickness is measured. A target thickness for the second layer is determined so that the optical properties of the combined actual first layer and target second layer are substantially the same as the optical properties of the combined nominal first layer and nominal second layer. The second layer is then deposited. Where the optical coating further includes a plurality of layer pairs, the steps of depositing, measuring, determining, and depositing are repeated for each of the layer pairs in the pairwise approach. Alternatively, in the layer-to-layer approach, for each layer pair after the initial layer pair the actual thickness of the second layer in the preceding layer pair is measured and a target thickness for the first layer is determined so that the optical properties of the combined actual preceding second layer and target first layer are substantially the same as the optical properties of the combined nominal preceding second layer and nominal first layer. The first layer is then deposited and its actual thickness measured. A target thickness for the second layer is determined so that the optical properties of the combined actual first layer and target second layer are substantially the same as the optical pro

Growing community of inventors

Newbury Park, CA, United States of America

Randolph L Hall