GB421620A - Improvements in magnifying lenses for reading purposes - Google Patents

Improvements in magnifying lenses for reading purposes

Info

Publication number
GB421620A
GB421620A GB2043933A GB2043933A GB421620A GB 421620 A GB421620 A GB 421620A GB 2043933 A GB2043933 A GB 2043933A GB 2043933 A GB2043933 A GB 2043933A GB 421620 A GB421620 A GB 421620A
Authority
GB
United Kingdom
Prior art keywords
face
reading purposes
magnifying
magnifying lenses
plane
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.)
Expired
Application number
GB2043933A
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to GB2043933A priority Critical patent/GB421620A/en
Publication of GB421620A publication Critical patent/GB421620A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B25/00—Eyepieces; Magnifying glasses
    • G02B25/002—Magnifying glasses

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Lenses (AREA)

Abstract

421,620. Magnifying -lenses. BIRCHALL, H. J., Glenwood, Oaks Road, Shirley, Surrey. July 20, 1933, No. 20439. [Class 97 (i)] A magnifying lens for reading purposes has a convex front surface 2 and a plane rear surface 5, the surface 2 being part of a surface of revolution generated by the rotation of an arc of a circle 3, Fig. 7, about its chord 4 which lies in the plane face 5, so that sections of the curved surface by planes at right-angles to the line 4 are circular arcs, the radii of which diminish continuously from the centre towards each end. The face 5 is in the form of an elongated strip which is connected to the edges of the face 1 by bevelled surfaces 6 coated with an opaque substance to bring the strip 5 into greater prominence. Projections 8 are provided to raise the face 5 above the surface to be viewed.
GB2043933A 1933-07-20 1933-07-20 Improvements in magnifying lenses for reading purposes Expired GB421620A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB2043933A GB421620A (en) 1933-07-20 1933-07-20 Improvements in magnifying lenses for reading purposes

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2043933A GB421620A (en) 1933-07-20 1933-07-20 Improvements in magnifying lenses for reading purposes

Publications (1)

Publication Number Publication Date
GB421620A true GB421620A (en) 1934-12-27

Family

ID=10145965

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2043933A Expired GB421620A (en) 1933-07-20 1933-07-20 Improvements in magnifying lenses for reading purposes

Country Status (1)

Country Link
GB (1) GB421620A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2521558A (en) * 1946-02-20 1950-09-05 Alvarez Patent Corp Magnifying picture viewing device
US4949978A (en) * 1988-11-25 1990-08-21 David Berner Magnifying device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2521558A (en) * 1946-02-20 1950-09-05 Alvarez Patent Corp Magnifying picture viewing device
US4949978A (en) * 1988-11-25 1990-08-21 David Berner Magnifying device

Similar Documents

Publication Publication Date Title
GB421620A (en) Improvements in magnifying lenses for reading purposes
GB529106A (en) Improvements in goggles
GB433710A (en) Tinted or coloured lenses
GB427737A (en) Improvements in connection with letters, designs, and the like for affixing to glassor other surfaces
GB477424A (en) Improvements in objectives
USD98686S (en) Design for a telescope
GB418083A (en) Improvements in or relating to multifocal lenses
GB442060A (en) Optical magnifying device
GB439302A (en) Lenses
GB472127A (en) Photographic lens system
GB413003A (en) Improvements in electric signs
GB460323A (en) Improvements in or relating to magnifying glasses
GB719709A (en) Improvements in night driving spectacle lenses
AU100177B2 (en) Improvements in lamp reflectors and lenses therefor
AU2417035A (en) Improvements in and connected with skyline advertising
AU41836A (en) Improvements in lamp reflectors and lenses therefor
GB348495A (en) Improvements in and relating to spectacles and eyeglasses
GB476349A (en) Improvements in or relating to photographic objectives
GB175414A (en) Improvements in and relating to illuminated signs or advertisements
AU100384B2 (en) Improvements in and connected with floating bridges
GB317200A (en) Improvements in or relating to optical slits such for example as are used in recording sound
AU101181B2 (en) Improvements in and connected with rifle sights
ES2322U (en) Optical toy that produces multiple symmetrical figures. (Machine-translation by Google Translate, not legally binding)
GB445498A (en) Improvements in or relating to light valves
GB371500A (en) Improvements in or applicable to spectacles