# US 10,308,051 B2 · Measurement device and printing apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,308,051 B2 - Document ID: US10308051B2 - Status: Granted - Kind: B2 - Application number: 15/466,229 - Filed: 2017-03-22 - Published: 2017-11-23 - Granted: 2019-06-04 - Earliest claimed: 2016-05-20 - Assignees: Seiko Epson Corporation - Applicants: Seiko Epson Corporation - Inventors: Tsugio Gomi - Web page: https://patentgrep.com/patent/US10308051B2 ## CPC - B41J 13/0009: {control of the transport of the copy material} - G01J 3/0202: {Mechanical elements; Supports for optical elements} - G01J 3/021: {using plane or convex mirrors, parallel phase plates, or particular reflectors} - G01J 3/027: {Control of working procedures of a spectrometer; Failure detection; Bandwidth calculation} - G01J 3/0289: {Field-of-view determination; Aiming or pointing of a spectrometer; Adjusting alignment; Encoding angular position; Size of measurement area; Position tracking} - G01J 3/10: Arrangements of light sources specially adapted for spectrometry or colorimetry - G01J 3/26: using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters - G01J 3/50: using electric radiation detectors - G01J 2003/102: {Plural sources} - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS - 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) ## Abstract A measurement device includes a light source that radiates an illumination light on a measurement object; and a measurement unit that measures a measurement light that is reflection light obtained by the illumination light being reflected by the measurement object or transmitted light obtained by the illumination light passing through the measurement object. The illumination light is a plurality of illumination lights. In a case where the measurement object is positioned at a reference position, an illumination center at which an optical axis of each of the plurality of illumination lights and the measurement object intersect, and a measurement center that is a center of a measurement region of the measurement object measured by the measurement unit are positioned at different positions. ## Claims ### Claim 1 A measurement device comprising: first and second light sources configured to-radiate first and second illumination directly onto a medium sheet, respectively, the first and second light sources being spaced apart from each other in a first direction; the first illumination light having a first optical axis at a first light incident angle with respect to the medium sheet; the second illumination light having a second optical axis at a second light incident angle with respect to the medium sheet; the first and second light incident angles being different from each other; and the first and second optical axes intersecting each other at a first point on the medium sheet when the medium sheet is located at a reference position; and a light receiver configured to receive first and second measurement lights created from only an irradiated measurement region of the medium sheet, a center of the irradiated measurement region corresponding to a measurement center in a plan view, the first and second measurement lights respectively corresponding to one of: first and second reflection lights that are obtained by reflecting the first and second illumination lights from the irradiated measurement region of the medium sheet; and first and second transmitted lights that are obtained by passing the first and second illumination lights through the irradiated measurement region of the medium sheet, wherein, when the medium sheet is positioned at the reference position, the measurement center is offset from the first point on the medium sheet, and the measurement center and the first point are on a first line extending in the first direction, and the light receiver is sandwiched between the first and second light sources in the first direction when viewed from a normal direction of the medium sheet. ### Claim 2 (depends on 1) The measurement device according to claim 1, wherein the first point is located inside the irradiated measurement region when viewed from the normal direction of the medium sheet. ### Claim 3 (depends on 1) The measurement device according to claim 1, wherein the first light source, the light receiver, and the second light source are located on the first line when viewed from the normal direction of the medium sheet. ### Claim 4 (depends on 1) The measurement device according to claim 1, wherein, when the medium sheet is positioned at a position closer to the light receiver by a first predetermined dimension along the normal direction of the medium sheet from the reference position, a first illumination center at which the first optical axis of the first illumination light and the medium sheet intersect is located at the measurement center. ### Claim 5 (depends on 1) The measurement device according to claim 1, wherein, when the medium sheet is positioned at a position further from the light receiver by a second predetermined dimension along the normal direction of the medium sheet from the reference position, a second illumination center at which the second optical axis of the second illumination light and the medium sheet intersect is located at the measurement center. ### Claim 6 (depends on 1) The measurement device according to claim 1, further comprising: a carriage on which the first and second light sources and the light receiver are mounted; and a moving mechanism that is configured to relatively move the carriage with respect to the medium sheet in a moving direction, wherein the first and second optical axes of the first and second illumination lights impinge upon the medium sheet on the first line when viewed from the normal direction of the medium sheet, and the moving direction is perpendicular to the first direction. ### Claim 7 A measurement device comprising: a light source that radiates an illumination light directly onto a medium sheet, an optical axis of the illumination light impinging upon a first point on the medium sheet when the medium sheet is positioned at a reference position; and first and second light receivers configured to receive first and second measurement lights, respectively, created from only an irradiated measurement region of the medium sheet, the first and second light receivers being spaced apart from each other in a first direction, a center of the irradiated measurement region corresponding to a measurement center in a plan view, the first and second measurement lights respectively corresponding to one of: first and second reflection lights that are obtained by reflecting the illumination light from the irradiated measurement region of the medium sheet; and first and second transmitted lights that are obtained by passing the illumination light through the irradiated measurement region of the medium sheet, wherein, when the medium sheet is positioned at the reference position, the measurement center is offset from the first point on the medium sheet, and the measurement center and the first point are on a first line extending in the first direction, and the light source is sandwiched between the first and second light receivers in the first direction when viewed from a normal direction of the medium sheet. ### Claim 8 A printing apparatus comprising: an image forming member that forms an image on a medium sheet; first and second light sources configured to radiate first and second illumination directly onto the medium sheet, respectively, the first and second light sources being spaced apart from each other in a first direction; the first illumination light having a first optical axis at a first light incident angle with respect to the medium sheet; the second illumination light having a second optical axis at a second light incident angle with respect to the medium sheet; the first and second light incident angles being different from each other; and the first and second optical axes intersecting each other at a first point on the medium sheet when the medium sheet is located at a reference position; and a light receiver configured to receive first and second measurement lights created from only an irradiated measurement region of the medium sheet, a center of the irradiated measurement region corresponding to a measurement center in a plan view, the first and second measurement lights respectively corresponding to one of: first and second reflection lights that are obtained by reflecting the first and second illumination lights from the irradiated measurement region of the medium sheet; and first and second transmitted lights that are obtained by passing the first and second illumination lights through the irradiated measurement region of the medium sheet, wherein, when the medium sheet is positioned at the reference position, the measurement center is offset from the first point on the medium sheet, and the measurement center and the first point are on a first line extending in the first direction, and the light receiver is sandwiched between the first and second light sources in the first direction when viewed from a normal direction of the medium sheet. ### Claim 9 (depends on 8) The printing apparatus according to claim 8, wherein the first point is located inside the irradiated measurement region when viewed from the normal direction of the medium sheet. ### Claim 10 (depends on 9) The printing apparatus according to claim 9, further comprising: a carriage on which the image forming member, the first and second light sources, and the light receiver are mounted; and a moving mechanism that relatively moves the carriage with respect to the medium sheet. ### Claim 11 (depends on 8) The printing apparatus according to claim 8, wherein the first light source, the light receiver, and the second light source are located on the first line when viewed from the normal direction of the medium sheet. ### Claim 12 (depends on 11) The printing apparatus according to claim 11, further comprising: a carriage on which the image forming member, the first and second light sources, and the light receiver are mounted; and a moving mechanism that relatively moves the carriage with respect to the medium sheet. ### Claim 13 (depends on 8) The printing apparatus according to claim 8, wherein, when the medium sheet is positioned at a position closer to the light receiver by a first predetermined dimension along the normal direction of the medium sheet from the reference position, a first illumination center at which the first optical axis of the first illumination light and the medium sheet intersect is located at the measurement center. ### Claim 14 (depends on 13) The printing apparatus according to claim 13, further comprising: a carriage on which the image forming member, the first and second light sources, and the light receiver are mounted; and a moving mechanism that relatively moves the carriage with respect to the medium sheet. ### Claim 15 (depends on 8) The printing apparatus according to claim 8, wherein, when the medium sheet is positioned at a position further from the light receiver by a second predetermined dimension along the normal direction of the medium sheet from the reference position, a second illumination center at which the second optical axis of the second illumination light and the medium sheet intersect is located at the measurement center. ### Claim 16 (depends on 15) The printing apparatus according to claim 15, further comprising: a carriage on which the image forming member, the first and second light sources, and the light receiver are mounted; and a moving mechanism that relatively moves the carriage with respect to the medium sheet. ### Claim 17 (depends on 8) The printing apparatus according to claim 8, further comprising: a carriage on which the first and second light sources and the light receiver are mounted; and a moving mechanism that is configured to relatively move the carriage with respect to the medium sheet in a moving direction, wherein the first and second optical axes of the first and second illumination lights impinge upon the medium sheet on the first line when viewed from the normal direction of the medium sheet, and the moving direction is perpendicular to the first direction. ### Claim 18 (depends on 8) The printing apparatus according to claim 8, further comprising: a carriage on which the image forming member, the first and second light sources, and the light receiver are mounted; and a moving mechanism that relatively moves the carriage with respect to the medium sheet.