Patent ID: 7072124

Claim:
A magnification loupe carried by a user wearable device, comprising: a housing having a first end with a first aperture for supporting an eyepiece lens, and a second end with a second aperture for supporting an objective lens; an eyepiece lens disposed in said first end of said housing; and an objective lens disposed in said second end of said housing; said objective lens having a non-circular shape, wherein at least two oppositely disposed arcuate first peripheral edges are defined by a first radius extending from a first center, and wherein at least two oppositely disposed arcuate second peripheral edges are defined by at least one second radius extending from at least a second center not coincident with said first center, said second radius having a length different from said first radius; said eyepiece lens comprising a single lens element; said objective lens comprising two lens elements; wherein said eyepiece lens and said objective lens are constructed and arranged according to the following parameters: Ele- Thick- Maximum ment Glass η d ν d Radius ness Diameter Sep. I Schott 1.589 61.3 R 1 = ∞ 2.2 12.0 NSK5 R 2 = ∞ II Schott 1.517 64.2 R 3 = 36.49 1.5 12.0 S 1 = 0.6 NBK7 R 4 = 18.48 III Schott 1.805 25.4 R 5 = 85.68 1.6 D 1 = 22.24 S 2 = 14.46 NSF56 R 6 = 39.71 D 2 = 23.60 IV Schott 1.517 64.2 R 7 = 39.71 6.65 D 3 = 23.60 NBK7 R 8 = 21.55 D 4 = 23.60 wherein the radius, thickness, and separation dimensions are given in millimeters; Roman numerals identify the lens elements in their respective order from an eyepoint side to an object side and element I is a representative correction lens; η d represents the refractive index of each element; η d is the abbe dispersion number; R 1 –R 8 represent the radii of respective refractive surfaces in order, from the eyepoint side to the object side; D 1 –D 4 represent the maximum clear lens aperture diameters of parent lens elements; and S 1 , S 2 represent the air space between the elements, measured along an optical centerline.