Document Type and Number:
Japanese Patent JPS5074443
Kind Code:
A
Abstract:
1425910 Diving spectacles OPTISCHE INDUSTRIE DE OUDE DELFT N V 27 Aug 1974 [7 Sept 1973] 37368/74 Heading G2J Two indentical optical systems comprise components 9 concave towards the image side and components 12 of positive power. The nodal point of the first component on the image side coincides with the nodal point of the second component on the object side and one of the spherical surfaces of each system is cospherical. The axes of the two systems lie at 40-60 degrees to each other and the optics (which are particularized) are such that the total drop line power of each system is virtually zero under water.
Application Number:
JP9193374A
Publication Date:
June 19, 1975
Filing Date:
August 10, 1974
Export Citation:
International Classes:
A63B33/00; B63C11/12; B63C11/48; G02B9/04; G02B13/18; G02B23/22; G02B27/02; G02C7/02; (IPC1-7): G02B3/04; G02B27/02; G02C7/02