← Back to Patent Explorer
JPH08562A Expired / Lapsed JP ⏱️ 0.0 years remaining

Position detection device for ophthalmologic equipment

Assignee: Canon Inc
•
Filing: 1994-06-23
•
Granted: —
•
Expires: 2014-06-23
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Translated from Japanese (57)【要約】 【目的】 角膜反射像間の中心位置と距離を算出する。 【構成】 被検眼Eの前眼部は対物レンズ群1、2及び レンズ6により撮像素子7上に結像している。また、光 源12から射出した光束は、投影レンズ11、ハーフミ ラー10を透過して、リレーレンズ9によりノズル5の 内部を通って、被検眼Eの角膜Ecを照明する。角膜Ecで 反射して形成された虚像Pは、対物レンズ群1、2によ り屈折され、ハーフミラー4を透過し、複数孔絞り5に より光束を分離される。複数孔絞り5の開口に対応した 一対のレンズ8b、8cは、角膜反射像Pを撮像素子7 上の2つの所定の位置に結像するので、これらの角膜反 射像間の中心位置と距離を算出する。 (57) [Summary] [Purpose] The center position and distance between corneal reflection images are calculated. [Arrangement] The anterior segment of the eye E is imaged on the image sensor 7 by the objective lens groups 1 and 2 and the lens 6. The light flux emitted from the light source 12 passes through the projection lens 11 and the half mirror 10, passes through the inside of the nozzle 5 by the relay lens 9, and illuminates the cornea Ec of the eye E to be inspected. The virtual image P formed by being reflected by the cornea Ec is refracted by the objective lens groups 1 and 2, transmitted through the half mirror 4, and separated by the multi-hole diaphragm 5. The pair of lenses 8b and 8c corresponding to the openings of the multi-hole aperture 5 capture the corneal reflection image P from the image sensor 7. Since the images are formed at the upper two predetermined positions, the center position and the distance between these corneal reflection images are calculated.

Inventors

  • 👤 Takashi Masuda
  • 👤 高 増田

Bibliographic Details

Application Number —
Jurisdiction JP
Data Source google_patents
Last Synchronized 2026-11-09 13:27
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/16; A61B3/165

Claims Analysis

Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag