JPS569717A - Optical filter device using liquid crystal - Google Patents

Optical filter device using liquid crystal

Info

Publication number
JPS569717A
JPS569717A JP8492879A JP8492879A JPS569717A JP S569717 A JPS569717 A JP S569717A JP 8492879 A JP8492879 A JP 8492879A JP 8492879 A JP8492879 A JP 8492879A JP S569717 A JPS569717 A JP S569717A
Authority
JP
Japan
Prior art keywords
liquid crystal
light
light beam
measuring
scattered light
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP8492879A
Other languages
Japanese (ja)
Inventor
Kiyoshi Yamada
Teruo Murakami
Masakata Minami
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toshiba Corp
Original Assignee
Toshiba Corp
Tokyo Shibaura Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toshiba Corp, Tokyo Shibaura Electric Co Ltd filed Critical Toshiba Corp
Priority to JP8492879A priority Critical patent/JPS569717A/en
Publication of JPS569717A publication Critical patent/JPS569717A/en
Pending legal-status Critical Current

Links

Landscapes

  • Investigating Materials By The Use Of Optical Means Adapted For Particular Applications (AREA)
  • Liquid Crystal (AREA)

Abstract

PURPOSE: To prevent misdetection without decreasing detecting sensitivity by using the optical element made by sandwiching a liquid crystal material in glass electrodes of simple construction.
CONSTITUTION: Light beam out from a light source 15 is made to parallel luminous fluxes by a collimator 16 and these luminous fluxes pass through deflectors 17, 18 as well as a scanning lens 19 and a half mirror 20, then scan the surface of a measuring sample 21 with a small light spot. The light beam reflected from the measuring sample 21 is reflected by the half mirror 20 and is condensed onto a space filter 23 by a condensing lens 22, whereby the scattered light components owing to the defects and dust on the measuring surface are separated. Nevertheless, the scattered light owing to the optical element is also included in this state; therefore, the measuring surface is imaged to an optical filter 25 by a liquid crystal by an imaging lens 24, by which the scattered light components produced in the light spot position on the measuring surface are separated and the light beam reaches a photodetector 26. The detection signal having been photoelectrically converted by said detector is processed in a processing circuit 27.
COPYRIGHT: (C)1981,JPO&Japio
JP8492879A 1979-07-06 1979-07-06 Optical filter device using liquid crystal Pending JPS569717A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP8492879A JPS569717A (en) 1979-07-06 1979-07-06 Optical filter device using liquid crystal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP8492879A JPS569717A (en) 1979-07-06 1979-07-06 Optical filter device using liquid crystal

Publications (1)

Publication Number Publication Date
JPS569717A true JPS569717A (en) 1981-01-31

Family

ID=13844348

Family Applications (1)

Application Number Title Priority Date Filing Date
JP8492879A Pending JPS569717A (en) 1979-07-06 1979-07-06 Optical filter device using liquid crystal

Country Status (1)

Country Link
JP (1) JPS569717A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0631129A1 (en) * 1993-06-22 1994-12-28 Österreichisches Forschungszentrum Seibersdorf Ges.m.b.H. Method and device for inspecting transparent objects

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0631129A1 (en) * 1993-06-22 1994-12-28 Österreichisches Forschungszentrum Seibersdorf Ges.m.b.H. Method and device for inspecting transparent objects

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