[go: up one dir, main page]

JPS54157639A - Pentagonal prism - Google Patents

Pentagonal prism

Info

Publication number
JPS54157639A
JPS54157639A JP6650178A JP6650178A JPS54157639A JP S54157639 A JPS54157639 A JP S54157639A JP 6650178 A JP6650178 A JP 6650178A JP 6650178 A JP6650178 A JP 6650178A JP S54157639 A JPS54157639 A JP S54157639A
Authority
JP
Japan
Prior art keywords
prism
pentagonal prism
faces
miniature
regions
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
JP6650178A
Other languages
Japanese (ja)
Inventor
Yasuo Yamazaki
Takeshi Egawa
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.)
Minolta Co Ltd
Original Assignee
Minolta 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 Minolta Co Ltd filed Critical Minolta Co Ltd
Priority to JP6650178A priority Critical patent/JPS54157639A/en
Publication of JPS54157639A publication Critical patent/JPS54157639A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/0018—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 with means for preventing ghost images

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Optical Elements Other Than Lenses (AREA)

Abstract

PURPOSE:To obtain a miniature prism which reflects light only in its effective optical path regions by forming the prism by the glass material whose refractive index and Abbe number are of a specified range and applying antireflection treatment to a part of the required reflecting faces. CONSTITUTION:When a pentagonal prism 1 is made by using glass whose refractive index is 1.55 to 1.60 and Abbe number is above 5.5, the prism ridgelines are sharply formed by easy fabrication and the critical angle of the total reflection surface becomes small, whereby the pentagonal prism is miniaturized. The regions other than the effective optical path regions of the roof faces 4, 5 and side faces 8, 9 making total reflection of light of the pentagonal prism 1 made in this way are black painted to prevent reflection. In addition, if reflection treatment by metal only on the third reflecting face 6 is made, ghosts and the like are not produced and the miniature and good prism suited for use in the finder optical system of cameras is provided.
JP6650178A 1978-06-01 1978-06-01 Pentagonal prism Pending JPS54157639A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6650178A JPS54157639A (en) 1978-06-01 1978-06-01 Pentagonal prism

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6650178A JPS54157639A (en) 1978-06-01 1978-06-01 Pentagonal prism

Publications (1)

Publication Number Publication Date
JPS54157639A true JPS54157639A (en) 1979-12-12

Family

ID=13317626

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6650178A Pending JPS54157639A (en) 1978-06-01 1978-06-01 Pentagonal prism

Country Status (1)

Country Link
JP (1) JPS54157639A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007045064A (en) * 2005-08-11 2007-02-22 Mitsubishi Pencil Co Ltd Writing utensil

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007045064A (en) * 2005-08-11 2007-02-22 Mitsubishi Pencil Co Ltd Writing utensil

Similar Documents

Publication Publication Date Title
JPS5564228A (en) Reflection type projecting screen
JPS5432319A (en) Fish eye lens
JPS55151601A (en) Pentagonal prism for camera finder
JPS5532023A (en) Reflecting-refracting lens system
KR880008400A (en) Cathode ray tube with antireflection film
JPS5498257A (en) Aspherical antireflection film
JPS52130631A (en) Photographic lens of large aperture and super wide angle
JPS5535336A (en) Wide angle zoom lens
JPS54157639A (en) Pentagonal prism
JPS57168214A (en) Albada finder
JPS5746203A (en) Optical switch
JPS57168235A (en) Photometric optical system of single-lens reflex camera
JPS55166632A (en) Finder for single-lens reflex camera
JPS5420750A (en) Photo coupler
JPS557727A (en) Planoconvex lens
JPS51144229A (en) Bright wide-angle lens with many surrounding quantities of light
JPS55105239A (en) Finder of single-lens reflex camera
JPS5538520A (en) Reflection-refraction type telephoto lens
JPS5696876A (en) Semiconductor light receiving element
JPS5499426A (en) Tessar type photographic lens
JPS5560912A (en) Spherical lens optical system
JPS5521077A (en) Photo switch
JPS5342845A (en) Photo coupling device
JPS57168213A (en) Reflecting telescope for camera
JPS57186710A (en) Optical circuit substrate and its manufacture