JPS57143248A - Projection type cathode-ray tube - Google Patents

Projection type cathode-ray tube

Info

Publication number
JPS57143248A
JPS57143248A JP2866881A JP2866881A JPS57143248A JP S57143248 A JPS57143248 A JP S57143248A JP 2866881 A JP2866881 A JP 2866881A JP 2866881 A JP2866881 A JP 2866881A JP S57143248 A JPS57143248 A JP S57143248A
Authority
JP
Japan
Prior art keywords
shutter
circumference
ray tube
luminance
correcting body
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
JP2866881A
Other languages
Japanese (ja)
Inventor
Yoshitaka Nakamura
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.)
NEC Home Electronics Ltd
NEC Corp
Original Assignee
NEC Home Electronics Ltd
Nippon 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 NEC Home Electronics Ltd, Nippon Electric Co Ltd filed Critical NEC Home Electronics Ltd
Priority to JP2866881A priority Critical patent/JPS57143248A/en
Priority to US06/338,205 priority patent/US4423438A/en
Priority to CA000394767A priority patent/CA1179724A/en
Publication of JPS57143248A publication Critical patent/JPS57143248A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B17/00—Systems with reflecting surfaces, with or without refracting elements
    • G02B17/08—Catadioptric systems
    • G02B17/0884—Catadioptric systems having a pupil corrector
    • G02B17/0888—Catadioptric systems having a pupil corrector the corrector having at least one aspheric surface, e.g. Schmidt plates
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B17/00—Systems with reflecting surfaces, with or without refracting elements
    • G02B17/08—Catadioptric systems
    • G02B17/0804—Catadioptric systems using two curved mirrors
    • G02B17/0808—Catadioptric systems using two curved mirrors on-axis systems with at least one of the mirrors having a central aperture
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G02B3/02—Simple or compound lenses with non-spherical faces
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/74—Projection arrangements for image reproduction, e.g. using eidophor
    • H04N5/7408—Direct viewing projectors, e.g. an image displayed on a video CRT or LCD display being projected on a screen

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Cathode-Ray Tubes And Fluorescent Screens For Display (AREA)

Abstract

PURPOSE:To improve resolution without reduction in luminance by a method wherein a circumferential portion of enlarged projected light sent out of a bulb and reflected from a mirror is partially screened and adjusted by an iris diaphragm of a shutter. CONSTITUTION:One piece of shutter is installed in the fron circumferential portion of a correcting body 14 in such a way that the shutter is freely rotatable and the circumference of the shutter is a true circle. A cylindrical portion 20a formed along the circumference inside the circle and the shutter are constructed in one body and an opening 20b of the true circle is formed, the opening 20b being eccentric with the circumference. In addition, because the cylindrical portion 20a is fixed along the peripheral side of a support 21 supporting the correcting body 14, the shutter 20 may turn on the center P of the correcting body 14. With this construction, luminance is not so much reduced and resolution can be improved by the adjustment of the iris diaphragm of the shutter.
JP2866881A 1981-02-26 1981-02-28 Projection type cathode-ray tube Pending JPS57143248A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP2866881A JPS57143248A (en) 1981-02-28 1981-02-28 Projection type cathode-ray tube
US06/338,205 US4423438A (en) 1981-02-26 1982-01-11 Projection type cathode ray tube with masking means
CA000394767A CA1179724A (en) 1981-02-26 1982-01-22 Projection type cathode ray tube with masking means

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2866881A JPS57143248A (en) 1981-02-28 1981-02-28 Projection type cathode-ray tube

Publications (1)

Publication Number Publication Date
JPS57143248A true JPS57143248A (en) 1982-09-04

Family

ID=12254885

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2866881A Pending JPS57143248A (en) 1981-02-26 1981-02-28 Projection type cathode-ray tube

Country Status (1)

Country Link
JP (1) JPS57143248A (en)

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