# US 2014/0193153 A1 · Methods and Apparatus to Multiplex Light Signals > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0193153 A1 - Document ID: US20140193153A1 - Status: Published application - Kind: A1 - Application number: 13/736,897 - Filed: 2013-01-08 - Published: 2014-07-10 - Earliest claimed: 2013-01-08 - Assignees: Schlumberger Technology Corporation - Applicants: Schlumberger Technology Corporation - Inventors: Yuji Hosoda - Web page: https://patentgrep.com/patent/US20140193153A1 ## CPC - H04J 14/00: Optical multiplex systems - E21B 49/08: Obtaining fluid samples or testing fluids, in boreholes or wells - G01V 8/00: Prospecting or detecting by optical means - G01V 8/24: using optical fibres - E21B 49/0875: {determining specific fluid parameters} - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) ## Abstract Methods and apparatus to multiplex light signals are disclosed herein. An example method includes conveying a first light signal via a first optical path and conveying a second light signal via a second optical path. The example method also includes frequency-division multiplexing and time-division multiplexing the first light signal and the second light signal to enable generation of a multiplexed light signal. The example method further includes directing the multiplexed light signal into an optical detector. ## Claims ### Claim 1 A method, comprising: conveying a first light signal via a first optical path; conveying a second light signal via a second optical path; frequency-division multiplexing and time-division multiplexing the first light signal and the second light signal to enable generation of a multiplexed light signal; and directing the multiplexed light signal into an optical detector. ### Claim 2 (depends on 1) The method of claim 1 wherein frequency-division multiplexing comprises modulating an intensity of the first light signal at a first frequency and modulating an intensity of the second light signal at a second frequency different than the first frequency. ### Claim 3 (depends on 1) The method of claim 1 further wherein time-division multiplexing the first light signal and the second light signal comprises interrupting the first light signal during a first time slot and interrupting the second light signal during a second time slot. ### Claim 4 (depends on 3) The method of claim 3 wherein interrupting the first light signal comprises operating an optical shutter. ### Claim 5 (depends on 1) The method of claim 1 further comprising: directing the first light signal to a first fluid sample to interact with the first fluid sample; and directing the second light signal to a second fluid sample to interact with the second fluid sample. ### Claim 6 (depends on 5) The method of claim 5 further comprising processing the multiplexed light signal to determine first information corresponding to the first fluid sample and second information corresponding to the second fluid sample. ### Claim 7 (depends on 1) The method of claim 1 wherein frequency-division multiplexing and time-division multiplexing comprises combining the first light signal and the second light signal in a third optical path. ### Claim 8 (depends on 2) The method of claim 2 wherein modulating the intensity of the first light signal comprises operating an optical chopper. ### Claim 9 A method, comprising: directing a light flux into a first fiber bundle, the first fiber bundle to split into a first fiber sub-bundle and a second fiber sub-bundle; chopping a first light signal communicated via the first fiber sub-bundle at a first frequency; shuttering the first light signal during a first time slot; chopping a second light signal communicated via the second fiber sub-bundle at a second frequency different than the first frequency; shuttering the second light signal during a second time slot different than the first time slot; and combining the first light signal and the second light signal to form a multiplexed light signal. ### Claim 10 (depends on 9) The method of claim 9 wherein chopping the first light signal comprises rotating an optical chopper disk. ### Claim 11 (depends on 9) The method of claim 9 wherein shuttering the first light signal comprises rotating an optical shutter disk. ### Claim 12 (depends on 9) The method of claim 9 further comprising: directing the multiplexed signal to an optical detector; and demultiplexing the multiplexed signal. ### Claim 13 (depends on 9) The method of claim 9 wherein the first fiber sub-bundle is in optical communication with a first fluid sample and further comprising interacting the first light signal with the fluid sample. ### Claim 14 An apparatus, comprising: a downhole tool; a first flowline and a second flowline disposed in the downhole tool; a first optical path to be in optical communication with a first fluid sample flowing through the first flowline; a second optical path to be in optical communication with a second fluid sample flowing through the second flowline, the first optical path and the second optical path to merge into a third optical path; an optical chopper disposed along at least one of the first optical path or the second optical path; an optical shutter disposed along at least one of the first optical path or the second optical path; and an optical detector in optical communication with the third optical path to receive a multiplexed light signal via the third optical path. ### Claim 15 (depends on 14) The apparatus of claim 14 further comprising a signal processor in communication with the optical detector to demultiplex the multiplexed light signal. ### Claim 16 (depends on 14) The apparatus of claim 14 wherein the optical shutter comprises a rotatable disk. ### Claim 17 (depends on 14) The apparatus of claim 14 wherein the optical chopper comprises a rotatable disk. ### Claim 18 (depends on 17) The apparatus of claim 17 wherein an opening ratio of the optical chopper is about one to one. ### Claim 19 (depends on 14) The apparatus of claim 14 further comprising a light source in optical communication with the first optical path and the second optical path. ### Claim 20 (depends on 14) The apparatus of claim 14 further comprising at least one optical fiber to define the first optical path.