# US 10,371,630 B2 · Inline concentration meter and concentration detection method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,630 B2 - Document ID: US10371630B2 - Status: Granted - Kind: B2 - Application number: 14/909,424 - Filed: 2014-07-18 - Published: 2016-06-16 - Granted: 2019-08-06 - Earliest claimed: 2013-07-31 - Assignees: Tokushima University; Fujikin Incorporated - Applicants: Tokushima University; Fujikin Incorporated - Inventors: Yoshihiro Deguchi; Masaaki Nagase; Nobukazu Ikeda; Michio Yamaji - Web page: https://patentgrep.com/patent/US10371630B2 ## CPC - G01N 21/5907: {Densitometers} - G01N 21/33: using ultraviolet light (G01N21/39 takes precedence) - G01N 2021/3148: {using three or more wavelengths} - G01N 2021/5969: {Scanning of a tube, a cuvette, a volume of sample} - G01N 2021/8411: {Application to online plant, process monitoring} - G01N 2021/8578: {Gaseous flow} - G01N 2201/0627: Use of several LED's for spectral resolution - G01N 2201/0691: Modulated (not pulsed supply) - 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 An inline concentration meter includes a light source unit emitting mixed light containing at least two wavelengths with a phase difference, a detecting unit including a light incident part for entering the mixed light emitted from the light source unit into a fluid passage of a detector body and at least two light detection parts receiving the mixed light passed through the fluid passage, a computing processor unit conducting frequency analyzes of detection signals of the mixed light output from the respective light detection parts and computing variations of intensities of the detection signals corresponding to absorbances in at least two frequency ranges to compute a concentration of fluid in the fluid passage based on the variations of the intensities of the detection signals, and a recording/displaying unit recording and displaying a value of the fluid concentration computed at the computing processor unit. ## Claims ### Claim 1 An inline concentration meter, comprising: a light source unit for emitting mixed light having at least two wavelengths with a phase difference; a detecting unit including a light incident part for entering the mixed light emitted from the light source unit into a fluid passage of a detector body and at least first and second light detection parts for receiving the mixed light emitted into the fluid passage, wherein a first light path through the fluid passage is defined between the light source and the first light detection part, and a second light path through the fluid passage, longer than the first light path, is defined between the light source and the second light detection part; wherein the second light path includes a first portion including the first light path and a second portion defined through the fluid passage between the first light detection part and the second light detection part; a computing processor unit for conducting frequency analyses of detection signals of the mixed light output from the respective light detection parts and computing variations of intensities of the detection signals corresponding to absorbances in at least two frequency ranges to compute a concentration of fluid in the fluid passage based on the variations of the intensities of detection signals in the at least two frequency ranges; wherein, from results of the frequency analyses through FFT (fast Fourier transformation) and/or the computed results of the variations of the light intensities corresponding to the absorbances in the respective frequency ranges, respective light absorption matrixes are obtained in the computing processor unit, and then the concentration of the raw material gas is continuously computed in real time based on the light absorption matrixes by using an algorithm for computing the raw material gas concentration; and a recording/displaying unit for recording and displaying a value of the fluid concentration computed at the computing processor unit; wherein, the light source unit emits ultraviolet light in a wavelength region of 200 nm to 400 nm; and wherein part of the mixed light is entered into the first light detection part through a light transmitting window of the first light detection part and part of the mixed light reflected on the light transmitting window is entered into the second light detection part. ### Claim 2 (depends on 1) The inline concentration meter according to claim 1, wherein the light source unit emits mixed light containing three wavelengths. ### Claim 3 (depends on 2) The inline concentration meter according to claim 2, wherein the one light incident part is arranged on one side of the detector body and three light detection parts are arranged on another side opposing to the one side. ### Claim 4 (depends on 1) The inline concentration meter according to claim 1, wherein the light source unit has an LED or laser diode as a light source. ### Claim 5 (depends on 1) The inline concentration meter according to claim 1, wherein the computing processor unit conducts the frequency analyses through Fourier transformation or wavelet transformation. ### Claim 6 (depends on 1) The inline concentration meter according to claim 1, wherein the computing processor unit computes a concentration of organic metal raw material gas included in the mixed gas flowing in the fluid passage. ### Claim 7 (depends on 1) The inline concentration meter according to claim 1, wherein the detecting unit comprises one light incident part and the first and second light detection parts. ### Claim 8 (depends on 7) The inline concentration meter according to claim 7, wherein the one light incident part is arranged on one side of the detector body and the first and second light detection parts are arranged on another side opposing to the one side. ### Claim 9 (depends on 7) The inline concentration meter according to claim 7, wherein the one light incident part and the second light detection part are arranged on one side of the detector body and the first light detection part is arranged on another side opposing to the one side. ### Claim 10 (depends on 1) The inline concentration meter according to claim 1, wherein the light source unit emits mixed ultraviolet light of three ultraviolet lights with different wavelengths. ### Claim 11 (depends on 1) The inline concentration meter according to claim 1, wherein the computing processor unit respectively conducts frequency analysis of detection signals of mixed light containing three wavelengths through Fourier transformation. ### Claim 12 (depends on 1) The inline concentration meter according to claim 1, wherein the light source unit emits mixed light that a beam combiner provides by combining ultraviolet lights with different wavelengths. ### Claim 13 A concentration detection method comprising the steps of: entering mixed light of three ultraviolet lights having different wavelengths with phase differences, emitted from a light source unit from one light incident part arranged on a detector body with a fluid passage, into the fluid passage; detecting the respective three ultraviolet lights passed through the fluid passage by at least first and second light detection parts arranged on the detector body, wherein a first light path through the fluid passage is defined between the light source and the first light detection part, and a second light path through the fluid passage, longer than the first light path, is defined between the light source and the second light detection part, wherein the second light path includes a first portion including the first light path and a second portion defined through the fluid passage between the first light detection part and the second light detection part; conducting frequency analyses of detection signals of the mixed light detected by the respective light detection parts; computing variations of intensities of the detection signals detected by the light detection parts corresponding to absorbances in three frequency ranges; and computing a concentration of organic metal material gas included in mixed gas that flows through the fluid passage based on the at least six computed variations of the intensities of the detection signals in the three frequency ranges. ### Claim 14 (depends on 13) The concentration detection method according to claim 13, wherein the number of the light detection parts is three and the concentration of the organic metal material gas included in the mixed gas that flows through the fluid passage is computed based on nine computed variations of intensities corresponding to the absorbances. ### Claim 15 (depends on 13) The concentration detection method according to claim 13, wherein the mixed light entering from the light incident part is detected by the first light detection part and reflected light from the first light detection part is entered to the second light detection part. ### Claim 16 (depends on 13) The concentration detection method according to claim 13, wherein the mixed light entering from the light incident part is dispersed and entered to the first and second light detection parts.