Stereomicroscopic inspection system with low eyestrain features

Claim 2

A stereomicroscopic inspection system with low eyestrain features comprising: a common objective means for forming an image of an object being inspected by a viewer and positioned a predetermined working distance adjacent to the object; first and second optical paths, each said path including: prism means positioned immediately adjacent to said common objective means for orienting said image viewed through said objective means along a heads-up axis; telephoto objective assembly means positioned adjacent said prism means for focusing of said image transmitted through said prism means; reticle means positioned adjacent said telephoto objective means, said telephone objective means focusing said image transmitted through said telephoto objective means onto said reticle means; and eyepiece means positioned adjacent said reticle means for providing heads-up viewing of the object by the viewer over a field of view, said eyepiece means including an instrument myopia corrector wedge, said wedge being disposed most proximate the viewer, said system focusing the image at a predetermined distance being substantially equal to the natural focusing distance of the eye.

Claim 3

The system according to claim 1 wherein said telephoto means and said eyepiece means are clipped.

Claim 4

The system according to claim 1 wherein said eyepiece means includes a pair of D shaped exit pupils having an interpupillary distance substantially equal to the average human interpupillary distance.

Claim 5

The system according to claim 3, whereby said exit pupils and the common acceptance angles thereof provide enhanced depth perception to the viewer.

Claim 6

The system according to claim 1, wherein the straight line distance from the viewer's eyes to the object is at least 75% of the predetermined distance, whereby eyestrain is reduced in alternating between unaided viewing and viewing through the system.

Claim 7

The system according to claim 1 wherein said working distance is at least 1.4 times its effective focal length.

Claim 8

The system according to claim 1, whereby said system provides the operator a sharp image over substantially the entire field of view.

Claim 9

The system according to claim 1, whereby said system provides the operator with freedom of head movement with respect to the field of view.

Claim 10

The system according to claim 1, said eyepiece means including a headsup display, whereby said system provides the viewer with ease of viewing and control over the object being viewed with respect to the field of view.

Claim 11

The system according to claim 1, said system including clipped telephoto objective assembly means and clipped eyepiece means, said clipped eyepiece means including large exit pupils, whereby the need for interpupillary adjustments is eliminated.

Claim 12

The system according to claim 1 wherein said system conforms substantially to the following table in which all elements have the characteristic values shown and, proceeding from the object to the eye of the viewer: __________________________________________________________________________ Glass Radius of Curvature Thickness Aperture Diameter Element Number Type Front Back at Vertex Front Back __________________________________________________________________________ (38) Working -- -- -- 3.600 -- -- Distance to object (24) Glare BK7 INF INF 0.250 5.450 5.450 Reduction Member (40) Space -- -- -- 1.235 -- -- (26) Objective SK16 2.1825 CC 3.7387 CX 0.350 3.550 4.340 Primary Lens (42) Space -- -- -- 0.040 -- -- (30) Objective LAFN2 INF Aspheric CX.sup.1 0.950 5.200 5.200 Secondary Lens (44) Space -- -- -- 1.559 -- -- (32) Objective SF57 8.3382 CC INF 0.280 5.500 6.300 Tertiary Lens (34) Objective SK16 INF 5.5826 CX 1.300 6.300 6.300 Quaternary Lens (46) Space -- -- -- 0.040 -- -- (36) Objective SK16 INF Aspheric CX.sup.2 1.000 6.500 6.500 Quinary Lens (52) Space -- -- -- 0.10 -- -- (48) Prism BAK1 INF INF 5.9750 3 × 3.5 3 × 3.5 (70) Space -- -- -- 0.100 -- -- (58) Telephoto SK16 4.6769 CX INF 0.700 4.00 4.00 Primary Lens (72) Space -- -- -- 0.04 -- -- (62) Telephoto SK16 3.7387 CX INF 0.750 3.800 3.800 Secondary Lens (74) Space -- -- -- 0.080 -- -- (64) Telephoto SF57 54.956 CC 4.5455 CC 0.180 3.800 3.460 Tertiary Lens (76) Space -- -- -- 2.069 -- -- (66) Telephoto SF4 3.3175 CX INF 0.500 2.880 2.880 Quaternary Lens (78) Space -- -- -- 0.0969 -- -- (68) Telephoto SK16 16.253 CC 1.6487 CC 0.200 2.600 2.100 Quinary Lens (80) Space -- -- -- 3.505 -- -- (18) Reticle BK7 INF INF 0.080 1.625 × 6.375 (Rectangular Front & Back (106) Space -- -- -- 0.375 -- -- (86) Eyepiece BK7 15.590 CX 1.8438 CC 1.125 2.40 2.600 Primary Lens (90) Eyepiece SF57 1.8438 CC INF 0.200 2.600 3.700 Secondary Lens (92) Eyepiece LAK21 INF 2.3979 CX 1.350 3.700 3.700 Tertiary Lens (98) Space -- -- -- 0.040 -- -- (94) Eyepiece LAK21 Aspheric CC.sup.3 INF 1.00 3.700 3.700 Quaternary Lens (96) Eyepiece FK5 INF INF 0.270 3.700 3.700 Quinary Lens (104) Space -- -- -- 2.934 -- -- to viewer (102) Exit .875 Pupil __________________________________________________________________________ Image Distance = -31.5 CC--Concave Surface CX--Convex Surface INF--Planar Surface Measurements are in inches. Positive distances are to the right and negative distances are to the left. The glass types are standard commercially available glass types, which are well known by the nomenclature used to those skilled in the art. The following polynomial defines the sag of curvature for the aspheric surfaces. ##STR2## Z = Sag of curvature of the lens Y = Radial distance from the vertex R = Base radius K = Conic constant A = Aspheric constant B = Aspheric constant C = Aspheric constant D = Aspheric constant The values for the aspheric surfaces are as follows: (1) R = 8.6459 CX (2) R = 8.966 CX (3) R = 2.6911 CX K = +3.1089 K = -2.427 K = -7.044 A = +3.213 × 10.sup.-4 A = -3.284 × 10.sup.-5 A = +2.212 × 10.sup.-2 B = -1.035 × 10.sup.-5 B = +1.883 × 10.sup.-6 B = -1.649 × 10.sup.-3 C = +1.903 × 10.sup.-6 C = +4.338 × 10.sup.-7 C = -3.936 × 10.sup.-4 D = 0 D = 0 D = +7.904 × 10.sup.-5