# US 2010/0163718 A1 · Method and apparatus for increasing the efficiency of a fluorescence measurement cell > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2010/0163718 A1 - Document ID: US20100163718A1 - Status: Published application - Kind: A1 - Application number: 12/346,037 - Filed: 2008-12-30 - Published: 2010-07-01 - Earliest claimed: 2008-12-30 - Assignees: Baker Hughes Incorporated - Inventors: Peter SCHAEFER; Stefan SROKA; Tobias KISCHKAT - Web page: https://patentgrep.com/patent/US20100163718A1 ## CPC - E21B 47/114: {using light radiation} - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract An apparatus for estimating a property of a fluid in an earth formation, the apparatus including: a logging instrument configured to be conveyed in a borehole penetrating the formation; and a plurality of light sources disposed at the logging instrument; wherein each of the light sources is configured to illuminate a sample of the fluid with a light beam causing the sample to fluoresce light with a characteristic related to the property, each of the light sources being configured to provide a light beam with a solid angle and a distance traveled to the sample, the solid angle and the distance being configured to concentrate the beam at an area of the sample that is overlapped substantially a same amount by a beam from another light source in the plurality. ## Claims ### Claim 1 An apparatus for estimating a property of a fluid in an earth formation, the apparatus comprising: a logging instrument configured to be conveyed in a borehole penetrating the formation; and a plurality of light sources disposed at the logging instrument; wherein each of the light sources is configured to illuminate a sample of the fluid with a light beam causing the sample to fluoresce light with a characteristic related to the property, each of the light sources being configured to provide a light beam with a solid angle and a distance traveled to the sample, the solid angle and the distance configured to concentrate the beam at an area of the sample that is overlapped substantially a same amount by a light beam from another light source in the plurality. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein each of the light sources is disposed at a bracket. ### Claim 3 (depends on 2) The apparatus of claim 2, wherein the bracket comprises an enhanced heat transfer capability. ### Claim 4 (depends on 3) The apparatus of claim 3, wherein the bracket comprises a material having enhanced heat transfer capability. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the material comprises a metal. ### Claim 6 (depends on 3) The apparatus of claim 3, wherein the bracket comprises fins for heat dissipation. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the plurality of light sources is disposed in a circular arrangement. ### Claim 8 (depends on 7) The apparatus of claim 7, further comprising at least a portion of a light detection device disposed at a center of the circular arrangement. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein the light detection device comprises at least one of a photodiode, a photomultiplier tube, a photoresistor, a phototransistor, a photovoltaic cell, and a charged-coupled device. ### Claim 10 (depends on 8) The apparatus of claim 8, wherein the light detection device comprises at least one of a fiber optic, lens optics, and free ray optics disposed at the center of the circular arrangement and coupled to at least one of a spectrometer and a fluorometer. ### Claim 11 (depends on 1) The apparatus of claim 1, wherein the plurality of light sources is disposed within a measurement cell, the measurement cell comprising an interior lined with a light reflecting material. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the light reflecting material comprises gold. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the light reflecting material comprises Spectralon®. ### Claim 14 (depends on 1) The apparatus of claim 1, wherein the plurality of light sources emits ultraviolet (UV) light. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein at least one light source comprises a light emitting diode (LED). ### Claim 16 (depends on 1) The apparatus of claim 1, wherein the area of the sample comprises substantially the entire area of the sample visible to the plurality of light sources. ### Claim 17 A method for estimating a property of a fluid in an earth formation, the method comprising: conveying a logging instrument in a borehole penetrating the formation, the logging instrument comprising a plurality of light sources configured to illuminate a sample of the fluid with light that causes the sample to fluoresce light, each of the light sources being configured to provide a light beam with a solid angle and a distance traveled to the sample, the solid angle and the distance being configured to concentrate the beam at an area of the sample that is overlapped substantially a same amount by a light beam from another light source in the plurality; illuminating the sample with light from the plurality of light sources; detecting light fluorescing from the sample; and estimating the property from the detected fluorescent light. ### Claim 18 (depends on 17) The method of claim 17, further comprising dissipating heat from the plurality of light sources with a bracket connected to the plurality of light sources. ### Claim 19 (depends on 17) The method of claim 17, further comprising reflecting the light emitted from the plurality of light sources with a reflecting material lining an interior surface of a measurement cell, the reflected light being directed towards the sample. ### Claim 20 A measurement cell for performing fluorescence spectroscopy on a sample of a material, the measurement cell comprising: a plurality of light sources configured to illuminate the sample with light causing the sample to fluoresce light, each of the light sources being configured to provide a light beam with a solid angle and a distance traveled to the sample, the solid angle and the distance being configured to concentrate the beam at an area of the sample that is overlapped substantially a same amount by a light beam from another light source in the plurality. ### Claim 21 (depends on 20) The measurement cell of claim 20, wherein the plurality of light sources is disposed in a circular arrangement. ### Claim 22 (depends on 21) The measurement cell of claim 21, wherein a light detection device is disposed within the circular arrangement.