Wide angle biocular eyepiece

Claim 2

A biocular eyepiece comprising four air spaced components including: a positive meniscus lens I convex to the observer; a cemented externally concave-convex doublet consisting of a positive lens II and negative lens III; a positive meniscus lens IV convex to the observer, and a positive concave-convex lens V convex to the observer.

Claim 3

An eyepiece according to claim 1 having an aperture of about F/1.0.

Claim 4

The eyepiece of claim 1 wherein the exit pupil is larger than the overall focal length of the device.

Claim 5

The eyepiece of claim 1 including means for establishing optical contact between said element V and an intermediate imaging means.

Claim 6

The eyepiece of claim 4 wherein said means comprises a plano-concave optic faceplate.

Claim 7

An eyepiece with substantially large apertures to permit biocular viewing of fields of view up to 60* from an eye relief distance of up to about 80 mm comprising five air spaced elements including: a positive meniscus lens convex to the observer designated I, a cemented externally concave-convex doublet consisting of a positive and a negative lens designated II and III respectively, a positive meniscus lens convex to the observer designated IV, and a positive concave-convex lens designated V; the value for the constructional data for said eyepiece being given substantially in the Tables of mathematical expressions herebelow wherein F1 to F5 respectively represent the equivalent focal length of lenses I to V, R1 to R9 respectively represent the radii of the successive lens surfaces of the lens I to V, t1 to t5 represent the axial thickness of lenses I to V, and S1 to S3 represent the successive interlens air spaces between the lenses: F1 2.667 t1 0.157 S1 0.035 F2 1.323 t2 0.313 S2 0.256 F3 1.418 t3 0.087 S3 0.017 F4 5.450 t4 0.157 F5 2.597 t5 0.122 R1 0.9857 R2 2.293 R3 0.8067 R4 38.52 R5 0.9523 R6 0.4810 R7 0.4908 R8 0.4305 R9 0.5009

Claim 8

An eyepiece with substantially large apertures to permit biocular viewing of fields of view up to 60* from an eye relief distance of up to about 80 mm comprising five air spaced elements including: a positive meniscus lens convex to the observer designated I, a cemented externally concave-convex doublet consisting of a positive and a negative lens designated II and III respectively, a positive meniscus lens convex to the observer designated IV, and a positive concave-convex lens designated V; the value for the constructional data for said eyepiece being given substantially in the Tables of mathematical expressions herebelow wherein F1 to F5 respectively represent the equivalent focal length of lenses I to V, R1 to R9 respectively represent the radii of the successive lens surfaces of the lens I to V, t1 to t5 represent the axial thickness of lenses I to V, and S1 to S3 represent the successive interlens air spaces between the lenses: F1 2.667 t1 0.157 S1 0.035 F2 1.323 t2 0.313 S2 0.256 F3 1.418 t3 0.087 S3 0.017 F4 5.450 t4 0.157 F5 2.597 t5 0.122 R1 0.9857 R2 2.293 R3 0.8067 R4 38.52 R5 0.9523 R6 0.4810 R7 0.4908 R8 0.4305 R9 0.5009