# US 12,192,609 B2 · Light source device and endoscope system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,192,609 B2 - Document ID: US12192609B2 - Status: Granted - Kind: B2 - Application number: 18/024,578 - Filed: 2021-09-22 - Published: 2023-10-05 - Granted: 2025-01-07 - Earliest claimed: 2020-10-27 - Assignees: Hoya Corporation - Applicants: Hoya Corporation - Inventors: Yoshihiro Hayashi; Yoshiyuki Niijima; Yukari Akino; Shinya Shimotashiro - Web page: https://patentgrep.com/patent/US12192609B2 ## CPC - A61B 1/0638: {providing two or more wavelengths} - H04N 23/555: {for picking-up images in sites, inaccessible due to their dimensions or hazardous conditions, e.g. endoscopes or borescopes} - A61B 1/0655: {Control therefor} - A61B 1/0684: {using light emitting diodes [LED]} - H04N 23/56: provided with illuminating means - H04N 23/73: by influencing the exposure time - H04N 23/74: by influencing the scene brightness using illuminating means - A61B 1/045: Control thereof - G02B 23/2461: {Illumination} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract A light source device that generates illumination light, the light source device including: a plurality of semiconductor light emitting elements that emit light beams having different wavelength bands; and a control unit that controls a light emission profile of the plurality of semiconductor light emitting elements and drives the plurality of semiconductor light emitting elements, in which the light emission profile includes a strong light emission period in which light emission is performed with a predetermined light intensity and a weak light emission period in which light emission is performed with a light intensity weaker than the predetermined light intensity, and the control unit executes a restoration control process of converting into a light emission amount in the strong light emission period while maintaining a total amount of the light emission amount in the strong light emission period and the light emission amount in the weak light emission period constant. ## Claims ### Claim 1 A light source device that generates illumination light with which an object is irradiated, the light source device comprising: a plurality of semiconductor light emitting elements that emit light beams having different wavelength bands from each other; and a control unit that controls a light emission profile of the plurality of semiconductor light emitting elements and drives the plurality of semiconductor light emitting elements, wherein the light emission profile includes a strong light emission period in which light emission is performed with a predetermined light intensity and a weak light emission period in which light emission is performed with a light intensity weaker than the predetermined light intensity, and the control unit executes a restoration control process of converting a light emission amount in the weak light emission period into a light emission amount in the strong light emission period while maintaining a total amount of the light emission amount in the strong light emission period and the light emission amount in the weak light emission period constant. ### Claim 2 (depends on 1) The light source device according to claim 1, wherein the control unit extends the strong light emission period by decreasing the light intensity in the weak light emission period and converting a light emission amount equal to the decreased intensity into the light emission amount in the strong light emission period while maintaining a length of the weak light emission period constant until the light intensity in the weak light emission period becomes zero. ### Claim 3 (depends on 1) The light source device according to claim 1, wherein the control unit extends the strong light emission period by shortening the weak light emission period and converting a light emission amount equal to the shortened period into the light emission amount in the strong light emission period while maintaining the light intensity in the weak light emission period constant. ### Claim 4 (depends on 1) The light source device according to claim 1, wherein the control unit extends the strong light emission period by shortening a length of the weak light emission period, and increasing the light intensity in the weak light emission period to convert the light emission amount in the weak light emission period as a light emission amount equal to the shortened period into the light emission amount in the strong light emission period. ### Claim 5 (depends on 1) The light source device according to claim 1, wherein after determining a light emission profile where a luminance value in a captured image falls within a predetermined range, the control unit sets the determined light emission profile as a target for starting the restoration control process. ### Claim 6 (depends on 1) The light source device according to claim 1, wherein the control unit simultaneously executes a process of determining a light emission profile where a luminance value in a captured image falls within a predetermined range, and the restoration control process performed on the light emission profile. ### Claim 7 (depends on 1) The light source device according to claim 1, wherein the control unit further executes a process of correcting linearity of an emitted light amount/electric current ratio of the plurality of semiconductor light emitting elements. ### Claim 8 (depends on 1) The light source device according to claim 1, wherein the control unit controls the plurality of semiconductor light emitting elements so as to perform offset light emission with a light emission intensity that is sufficiently lower than a light emission intensity in the strong light emission period and does not generate a double-exposure image, but in a case where the object is close, allows the object to be visually recognized during a non-light emission period other than the weak light emission period and the strong light emission period or during a weak light emission period in which a light emission intensity is so weak that light emission is not visually recognizable. ### Claim 9 (depends on 8) The light source device according to claim 8, wherein the control unit executes the offset light emission with pulsed light or continuous light. ### Claim 10 An endoscope system that inserts an endoscope into an observation target and acquires an image of an object, the endoscope system comprising: a plurality of semiconductor light emitting elements that emit light beams having different wavelength bands from each other; an image sensor that irradiates the object with illumination light and detects reflected light from the object to generate an image signal; a processor that processes the image signal to generate the image of the object and displays the image on a monitor; a main control unit that generates a control signal for controlling a light emission profile of the plurality of semiconductor light emitting elements on the basis of the image signal; and a light source control unit that receives the control signal from the main control unit and drives the plurality of semiconductor light emitting elements with a drive signal according to the light emission profile, wherein the light emission profile includes a strong light emission period in which light emission is performed with a predetermined light intensity and a weak light emission period in which light emission is performed with a light intensity weaker than the predetermined light intensity, and the main control unit determines the light emission profile by executing a restoration control process of converting a light emission amount in the weak light emission period into a light emission amount in the strong light emission period while maintaining a total amount of the light emission amount in the strong light emission period and the light emission amount in the weak light emission period constant. ### Claim 11 (depends on 10) The endoscope system according to claim 10, wherein the main control unit generates the control signal for extending the strong light emission period by decreasing the light intensity in the weak light emission period and converting a light emission amount equal to the decreased intensity into the light emission amount in the strong light emission period while maintaining a length of the weak light emission period constant until the light intensity in the weak light emission period becomes zero. ### Claim 12 (depends on 10) The endoscope system according to claim 10, wherein the main control unit generates the control signal for extending the strong light emission period by shortening the weak light emission period and converting a light emission amount equal to the shortened period into the light emission amount in the strong light emission period while maintaining the light intensity in the weak light emission period constant. ### Claim 13 (depends on 10) The endoscope system according to claim 10, wherein the main control unit generates the control signal for extending the strong light emission period by shortening a length of the weak light emission period, and increasing the light intensity in the weak light emission period to convert the light emission amount in the weak light emission period as a light emission amount equal to the shortened period into the light emission amount in the strong light emission period. ### Claim 14 (depends on 10) The endoscope system according to claim 10, further comprising a photometric unit that acquires luminance value information using the image signal, wherein the main control unit acquires the luminance value information from the photometric unit, determines a light emission profile where a luminance value in the image signal falls within a predetermined range, and sets the determined light emission profile as a target for starting the restoration control process. ### Claim 15 (depends on 10) The endoscope system according to claim 10, wherein the main control unit further generates a control signal for controlling the plurality of semiconductor light emitting elements so as to perform offset light emission with a light emission intensity that is sufficiently lower than a light emission intensity in the strong light emission period and does not generate a double-exposure image, but in a case where the object is close, allows the object to be visually recognized during a non-light emission period other than the weak light emission period and the strong light emission period or during a weak light emission period in which a light emission intensity is so weak that light emission is not visually recognizable, and outputs the control signal to the light source control unit.