# US 10,309,828 B2 · Spectrometer with active beam steering > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,309,828 B2 - Document ID: US10309828B2 - Status: Granted - Kind: B2 - Application number: 15/730,548 - Filed: 2017-10-11 - Published: 2018-05-10 - Granted: 2019-06-04 - Earliest claimed: 2014-08-22 - Assignees: SpectraSensors, Inc. - Applicants: SpectraSensors, Inc. - Inventors: Alfred Feitisch; Xiang Liu; Keith Benjamin Helbley; Douglas Beyer - Web page: https://patentgrep.com/patent/US10309828B2 ## CPC - G01J 3/0205: {Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows} - G01J 3/0237: {Adjustable, e.g. focussing} - G01J 3/027: {Control of working procedures of a spectrometer; Failure detection; Bandwidth calculation} - G01J 3/0278: {Control or determination of height or angle information for sensors or receivers} - G01J 3/0291: {Housings; Spectrometer accessories; Spatial arrangement of elements, e.g. folded path arrangements} - G01J 3/42: Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry (beam switching arrangements G01J3/08) - G01N 21/31: Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry {(G01N21/72 takes precedence)} - G01J 2003/421: {Single beam} - G01N 2201/06113: Coherent sources; lasers - G01N 2201/062: LED's - G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N) - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract A spectrometer includes a light source that emits a beam into a sample volume comprising an absorbing medium. Thereafter, at least one detector detects at least a portion of the beam emitted by the light source. It is later determined, based on the detected at least a portion of the beam and by a controller, that a position and/or an angle of the beam should be changed. The beam emitted by the light source is then actively steered by an actuation element under control of the controller. In addition, a concentration of the absorbing media can be quantified or otherwise calculated (using the controller or optionally a different processor that can be local or remote). The actuation element(s) can be coupled to one or more of the light source, a detector or detectors, and a reflector or reflectors intermediate the light source and the detector(s). ## Claims ### Claim 1 An apparatus comprising: a light source configured to emit a beam into a channel comprising an absorbing medium, wherein the light source is a tunable diode laser; at least one detector positioned to detect at least a portion of the beam emitted by the tunable diode laser, wherein the tunable diode laser and the detector are positioned on opposing sides of the channel in an open path configuration; at least one actuation element configured to selectively cause the beam emitted by the tunable diode laser to be steered; and a controller coupled to the at least one actuation element, the controller configured to: determine that a path of the beam should be steered based on at least one of an intensity level and a position of the beam detected by the at least one detector; identify a divergence of the path of the beam and/or optical diffraction and/or an interference along the path of the beam; and cause the at least one actuation element to steer the beam to adjust the position and/or an angle of the beam to correct the divergence and/or the optical diffraction and/or the interference along the path of the beam in response to the position and/or an angle of the beam that is detected by the detector. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the at least one actuation element is coupled to the light source and/or the at least one detector. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the at least one actuation element is coupled to a transmissive optical element and/or a reflective optical element. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the absorbing medium comprises a gas, a liquid, a reflective media, an emitting media, and/or a Raman active media. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the at least one actuation element comprises at least one piezo element. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the at least one actuation element comprises a stepper motor, an electro-optical actuator, an acousto-optical actuator, a micro-electro-mechanical systems (MEMS) actuation device, an inch-worm, a mechanical actuator, a magnetic actuator, an electrostatic actuator, an inductive actuator, a rotary actuator, a heated actuator, a pressure actuator, a stress and strain actuator, and/or an analog motor. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the at least one actuation element comprises or is coupled to a prism, an etalon, a lens, one or more gratings, a diffractive optical element, a reflector, a birefringent element, a crystal element, an amorphous element, an electro-optic element, an acousto-optic element, an optical window, an optical wedge, a waveguide, an adjustable waveguide, an electrically manipulated waveguide, and/or an air waveguide. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the steering of the beam comprises adjusting the position of the beam in accordance with a pre-defined x-y position and/or adjusting the angle of the beam in accordance with a pre-defined x-y angle. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein the controller is further configured to cause the at least one actuation element to maintain the position of the beam at a pre-defined x-y position and/or maintain the angle of the beam at a pre-defined x-y angle. ### Claim 10 (depends on 1) The apparatus of claim 1, wherein the at least one detector comprises an array of photoreceivers, a multi-element photoreceiver, and/or at least one position sensing photodiode. ### Claim 11 (depends on 1) The apparatus of claim 1, wherein the at least one detector comprises an indium gallium arsenide (InGaAs) detector, an indium arsenide (InAs) detector, an indium phosphide (InP) detector, a silicon (Si) detector, a silicon germanium (SiGe) detector, a germanium (Ge) detector, a mercury cadmium telluride detector (HgCdTe or MCT), a lead sulfide (PbS) detector, a lead selenide (PhSe) detector, a thermopile detector, a multi-element array detector, a single element detector, a CMOS (complementary metal oxide semiconductor) detector, a CCD (charge coupled device detector) detector, and/or a photo-multiplier. ### Claim 12 (depends on 1) The apparatus of claim 1, wherein steering of the beam comprises changing an overall beam path length. ### Claim 13 A method comprising: emitting, by a tunable diode laser, a beam into a channel comprising an absorbing medium; traversing the channel by the beam a single time in an open path system configuration; detecting, by at least one detector, at least a portion of the beam emitted by the tunable diode laser; determining, by a controller, that a path of the beam should be steered based on at least one of an intensity level and a position of the beam, the determining comprising identifying a divergence in the path of the beam, an optical diffraction along the path of the beam, and/or the interference along the path of the beam; and selectively steering, by at least one actuation element coupled with the controller, the beam to adjust the position and/or an angle of the beam, the position and/or the angle of the beam being adjusted in order to correct the divergence, the optical diffraction, and/or the interference, the beam being steered in response to the position and/or the angle of the beam that is detected by the detector.