# US 2017/0285318 A1 · Imaging system and imaging method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0285318 A1 - Document ID: US20170285318A1 - Status: Published application - Kind: A1 - Application number: 15/455,934 - Filed: 2017-03-10 - Published: 2017-10-05 - Earliest claimed: 2016-04-01 - Assignees: Mitutoyo Corporation - Applicants: Mitutoyo Corporation - Inventors: Gyokubu CHO; Tatsuya NAGAHAMA; Takahisa OOTAKE; Kazuki KITAGAWA - Web page: https://patentgrep.com/patent/US20170285318A1 ## CPC - G02B 21/245: {using auxiliary sources, detectors} - G02B 21/025: {with variable magnification (variable magnification G02B15/00)} - G02B 21/361: {Optical details, e.g. image relay to the camera or image sensor (G02B21/364 takes precedence; illumination details G02B21/06 and subgroups)} - G02B 21/365: {Control or image processing arrangements for digital or video microscopes (G02B21/361, G02B21/362 take precedence)} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract An imaging system includes: an image forming device that obtains image information of an object with the focal length to the object being changed by a variable focal length lens in an optical system, so as to form an all-focused image of the object; a sensor device that detects variations in the surface level of the object in a focus direction; and a position adjustment device that adjusts the position of the object in the focus direction in accordance with the surface level variations of the object detected by the sensor device. The position adjustment device adjusts the position of the object in the focus direction in such a manner that the surface level of the object becomes closer to the center of a variable focal length range of the variable focal length lens. ## Claims ### Claim 1 An imaging system comprising: an image forming device comprising an optical system having a variable focal length lens capable of changing a focal length to an object within a predetermined range, the image forming device obtaining image information of the object with the focal length being changed by the variable focal length lens, and forming an all-focused image of the object; a sensor device that detects variations in a surface level of the object in a direction of focus; and a position adjustment device that adjusts a position of the object in the direction of focus in accordance with the surface level variations of the object detected by the sensor device, wherein the position adjustment device adjusts the position of the object in the direction of focus in a manner such that the surface level of the object becomes closer to the center of a variable focal length range of the variable focal length lens. ### Claim 2 (depends on 1) The imaging system according to claim 1, wherein the sensor device detects that the surface level of the object has moved within the variable focal length range by a predetermined threshold from the center of the variable focal length range, and wherein the position adjustment device adjusts the position of the object in the direction of focus when the sensor device detects that the surface level of the object has moved by the predetermined threshold. ### Claim 3 (depends on 2) The imaging system according to claim 2, wherein the predetermined threshold is set as distances away in opposite directions from the center of the variable focal length range. ### Claim 4 (depends on 1) The imaging system according to claim 1, wherein the position adjustment device adjusts the position of the object in the direction of focus in a manner such that the surface level of the object agrees with the center of the variable focal length range. ### Claim 5 (depends on 1) The imaging system according to claim 1, wherein the sensor device includes a laser light source that applies laser light to the object and a photodiode that receives the laser light reflected from the object. ### Claim 6 (depends on 1) The imaging system according to claim 1, wherein the position adjustment device includes a moving device that moves the position of the object in the direction of focus, and a position controller that controls the moving device so as to adjust the position of the object in the direction of focus. ### Claim 7 An imaging method comprising the steps of: obtaining image information of an object with a focal length to the object being changed by using a variable focal length lens provided in an optical system, so as to form an all-focused image of the object; detecting variations in a surface level of the object in a direction of focus; and in response to the variations in the surface level of the object, adjusting a position of the object in the direction of focus in a manner such that the surface level of the object becomes closer to the center of a variable focal length range of the variable focal length lens. ### Claim 8 (depends on 7) The imaging method according to claim 7, wherein the position of the object in the direction of focus is adjusted when the surface level of the object moves within the variable focal length range by a predetermined threshold from the center of the variable focal length range. ### Claim 9 (depends on 8) The imaging method according to claim 8, wherein the predetermined threshold is set as distances away in opposite directions from the center of the variable focal length range. ### Claim 10 (depends on 7) The imaging method according to claim 7, wherein the position of the object in the direction of focus is adjusted in a manner such that the surface level of the object agrees with the center of the variable focal length range. ### Claim 11 (depends on 2) The imaging system according to claim 2, wherein the position adjustment device adjusts the position of the object in the direction of focus in a manner such that the surface level of the object agrees with the center of the variable focal length range. ### Claim 12 (depends on 3) The imaging system according to claim 3, wherein the position adjustment device adjusts the position of the object in the direction of focus in a manner such that the surface level of the object agrees with the center of the variable focal length range. ### Claim 13 (depends on 2) The imaging system according to claim 2, wherein the sensor device includes a laser light source that applies laser light to the object and a photodiode that receives the laser light reflected from the object. ### Claim 14 (depends on 3) The imaging system according to claim 3, wherein the sensor device includes a laser light source that applies laser light to the object and a photodiode that receives the laser light reflected from the object. ### Claim 15 (depends on 2) The imaging system according to claim 2, wherein the position adjustment device includes a moving device that moves the position of the object in the direction of focus, and a position controller that controls the moving device so as to adjust the position of the object in the direction of focus. ### Claim 16 (depends on 3) The imaging system according to claim 3, wherein the position adjustment device includes a moving device that moves the position of the object in the direction of focus, and a position controller that controls the moving device so as to adjust the position of the object in the direction of focus. ### Claim 17 (depends on 8) The imaging method according to claim 8, wherein the position of the object in the direction of focus is adjusted in a manner such that the surface level of the object agrees with the center of the variable focal length range. ### Claim 18 (depends on 9) The imaging method according to claim 9, wherein the position of the object in the direction of focus is adjusted in a manner such that the surface level of the object agrees with the center of the variable focal length range.