# US 2019/0377254 A1 · Inspection assembly viewport > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0377254 A1 - Document ID: US20190377254A1 - Status: Published application - Kind: A1 - Application number: 16/479,051 - Filed: 2018-01-19 - Published: 2019-12-12 - Earliest claimed: 2017-01-20 - Assignees: E.V. Offshore Limited - Applicants: E.V. Offshore Limited - Inventors: Jonathan THURSBY; Shaun PECK; Jonathan Brian RUDD - Web page: https://patentgrep.com/patent/US20190377254A1 ## CPC - E21B 47/002: by visual inspection - G03B 37/005: {Photographing internal surfaces, e.g. of pipe, (G03B37/02 - G03B37/06 take precedence; instruments for performing medical examinations of cavities or tubes of the body by photographic inspection A61B1/00)} - E21B 47/017: Protecting measuring instruments - F16L 2101/30: Inspecting, measuring or testing - G03B 2215/0517: Housing - G03B 2215/0567: Solid-state light source, e.g. LED, laser - G03B 2215/0571: With second light source - G03B 2215/0575: Ring shaped lighting arrangements - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) - F16L: PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL ## Abstract Inspection assemblies that include one or more sideview cameras for capturing images of an interior surface of a pipe or conduit include an elongate housing, a sideview camera within the housing and arranged to capture an image of a region within a field of view external to the housing, and a viewport element mounted in the housing and located such that light is transmitted through the viewport element and into said sideview camera, wherein the viewport element has a concave internal surface, closer to the camera, and a convex external surface, further from the camera, and wherein the centre of the radius of curvature of the internal surface is closer to the viewport element than the centre of the radius of curvature of the external surface. ## Claims ### Claim 1 An inspection assembly for imaging the internal surface of a pipe or conduit comprising: an elongate housing; a sideview camera within the housing and arranged to capture an image of a region within a field of view external to the housing; and a viewport element mounted in the housing and located such that light is transmitted through the viewport element and into said sideview camera, wherein the viewport element has a concave internal surface, closer to the camera, and a convex external surface, further from the camera, and wherein the centre of the radius of curvature of the internal surface is closer to the viewport element than the centre of the radius of curvature of the external surface. ### Claim 2 (depends on 1) An inspection assembly as claimed in claim 1, wherein the viewport element is made of sapphire. ### Claim 3 (depends on 1) An inspection assembly as claimed in claim 1, wherein the sideview camera is mounted such that the centre line of the field of view extends in a direction substantially perpendicular to a longitudinal axis of the housing. ### Claim 4 (depends on 1) An inspection assembly as claimed in claim 1, wherein the housing is substantially cylindrical. ### Claim 5 (depends on 1) An inspection assembly as claimed in claim 1, further comprising a plurality of sideview cameras. ### Claim 6 (depends on 5) An inspection assembly as claimed in claim 5, wherein the cameras are arranged in a circumferential array. ### Claim 7 (depends on 1) An inspection assembly as claimed in claim 1, further comprising a light source disposed at a location spaced apart from the sideview camera along a longitudinal axis of the housing. ### Claim 8 (depends on 7) An inspection assembly as claimed in claim 7, further comprising a second light source and wherein a first light source is disposed on a first side of the camera and the second light source is disposed on a second side of the camera. ### Claim 9 (canceled) ### Claim 10 (depends on 8) An inspection assembly as claimed in claim 8, wherein a line extending between the first and second light sources extends parallel to the longitudinal axis of the housing. ### Claim 11 (depends on 7) An inspection assembly as claimed in claim 7, wherein the or each light source is angled such that a centre line of a beam of light emitted by the light source is at an angle of less than 90° to the longitudinal axis of the housing. ### Claim 12 (depends on 10) An inspection assembly as claimed in claim 10, wherein the first and second light sources are angled such that centre lines of the beams of light emitted by the light sources are convergent. ### Claim 13 (depends on 7) An inspection assembly as claimed in claim 7, wherein the light source comprises a plurality of light emitters arranged in a circumferential array and wherein the plurality of light emitters are disposed around a circumferential region of the housing and the light emitters are configured to emit light in a radially outwards direction such that an annular region surrounding the housing is illuminated. ### Claim 14 (canceled) ### Claim 15 (depends on 13) An inspection assembly as claimed in claim 13, comprising a first circumferential array of light emitters lying in a first plane on a first side of the cameras and a second circumferential array of light emitters lying in a second plane on a second side of the cameras, the first and second planes being substantially perpendicular to the longitudinal axis and the first and second planes being spaced apart along the longitudinal axis. ### Claim 16 (depends on 7) An inspection assembly as claimed in claim 7, further comprising a window element mounted in the housing, the window element comprising a light transmitting material and being located such that light emitted by the light source or at least one of said light sources passes through the window element before illuminating the field of view. ### Claim 17 (depends on 16) An inspection assembly as claimed in claim 16, wherein the window element is annular. ### Claim 18 (depends on 17) An inspection assembly as claimed in claim 17, wherein the internal surface of the annular window element is cylindrical. ### Claim 19 (depends on 16) An inspection assembly as claimed in claim 16, wherein an external surface of the window element comprises a concave region. ### Claim 20 (depends on 1) A downhole tool for imaging the internal surface of a borehole or casing comprising an inspection assembly as claimed in claim 1 connected to and deployed on electric line, slickline, or coiled tubing. ### Claim 21 (depends on 20) A downhole tool as claimed in claim 20 further comprising a bore configured to allow a flow of fluid through the tool. ### Claim 22 (depends on 20) A tool string comprising a downhole tool as claimed in claim 20 and at least one other downhole tool.