OPTICAL SENSOR AND IMAGE FORMING APPARATUS

• Main Authors: YAGUCHI KAZUTAKA, INAO KAZUSHI, KITA HIROSHI, MUKOHARA TAKUYA, ASAMI JUNYA
• Format: Patent
• Language: English; Japanese
• Published: 02.09.2021
• Subjects: BASIC ELECTRIC ELEMENTS; CINEMATOGRAPHY; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; HOLOGRAPHY; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MAGNETOGRAPHY; MEASURING; PHOTOGRAPHY; PHYSICS; SEMICONDUCTOR DEVICES; TESTING

To prevent a reduction in detection accuracy that may be caused by reflected light from a surface to be irradiated in an optical sensor, such as a toner sensor.SOLUTION: A circuit board is mounted with a light emitting device and a light receiving unit. A housing has a first opening and a second opening. The first opening is provided in a first light guide path arranged between the light emitting device and a surface to be irradiated and is arranged such that light output from the light emitting device is directed to the surface to be irradiated. The second opening is provided in a second light guide path arranged between the surface to be irradiated and the light receiving unit. The first opening is an emission port of a through hole provided to penetrate the housing. The shape of the through hole is a shape in which diffraction light having an order of diffraction of +1 or more and diffraction light having an order of diffraction of -1 or more generated on the surface to be irradiated are not incident on the light receiving unit.SELECTED DRAWING: Figure 9 【課題】トナーセンサなどの光学センサにおいて被照射面からの反射光によって生じうる検知精度の低下を抑制すること。【解決手段】回路基板には発光素子、および受光ユニットが実装される。ハウジングは、第一開口と第二開口を有している。第一開口は、発光素子と被照射面との間に配置された第一導光路に設けられ、発光素子から出力された光が前照射面に向かうように、配置される。第二開口は、被照射面と受光ユニットとの間に配置された第二導光路に設けられる。第一開口は、ハウジングを貫通するように設けられた貫通孔の出射口である。貫通孔の形状は、被照射面に生じる＋１次以上の次数の回折光と−１次以上の回折光とが受光ユニットに入射しない形状である。【選択図】 図９