Night vision goggle system

• US 4,463,252 A
• Filed: 01/04/1982
• Issued: 07/31/1984
• Est. Priority Date: 01/04/1982
• Status: Expired due to Term

• Current Assignee: Baird Corporation
• Original Assignee: Baird Corporation
• Inventors: Brennan, Thomas M., Burley, Robert M.
• Primary Examiner(s): Nelms, David C.
• Assistant Examiner(s): Austin, II, E.
• Application Number:
  US06/337,023
• Time in Patent Office: 939 Days
• Field of Search: 350/538, 350/547, 350/548, 350/549, 350/474, 350/475, 350/476, 350/145, 250/213 VT, 250/341, 313/523, 313/524
• US Class Current: 250/214.0VT
• CPC Class Codes: G02B 23/12 with means for image conversion or intensification
• CPC Class Codes: G02B 23/125 head-mounted

Abstract

A night vision goggle system comprising a housing, an optical system accommodated therein and including a pair of eyepiece assemblies, with each assembly slidably mounted for interpupillary adjustment. The assemblies are respectively focusable. The optical system further includes an objective lens assembly, an image intensifier tube provided with concave-faced fiber optics, and a collimator lens assembly, all in axial alignment, and a splitter member. The objective, collimator and eyepiece assemblies feature prescription optics.

The goggle system preferably is head mounted via a quick-release connection to a face mask provided with an adjustable strap assembly.

Claims

1. A night vision goggle system comprising:

(a) a housing;

(b) an optical system accommodated within said housing, said system including a pair of eyepiece assemblies;

(c) each of said pair of eyepiece assemblies slidably mounted within said housing for individual lateral adjustment of interpupillary distance;

(d) said optical system comprising an objective lens assembly, an image intensifier tube, and a collimator lens assembly, all mounted in optical axial alignment; and

(e) a splitter member mounted concentric with said optical axial alignment.

2. The night vision goggle system of claim 1 further including means operatively associated with each of said pair of eyepiece assemblies for providing individual focusing thereto, and wherein each of said pair of eyepiece assemblies includes an individually adjustable focusing subassembly from +2 to -6 diopter, a flat replicated mirror and a second subassembly.

3. The night vision goggle system of claim 1 further including means for providing a wide field of view illumination designed for short distances, said means including visible indication via said optical system that said illumination is operational.

4. The night vision goggle system of claim 3 further including a detachable optical accessory designed to be mounted over said means for providing said wide field of view illumination to modify the same to a narrow field of view illumination at distances between about 100 to about 250 yards.

5. The night vision goggle system of claim 1 further including a face mask having an adjustable strap assembly, a connection designed removably to mount said housing to said face mask, and wherein said connection is of a quick-release type and being provided with a plurality of indented stops, and wherein said strap assembly is adjustable via a six-point connection to said face mask.

6. The night vision goggle system of claim 1 wherein said housing is so constructed as to enable said goggle system to be operational over a temperature range of about +45°

C. to about -45°

C. and in an environment of up to 99% humidity, including the capability of being immersed for up to three feet in water without adverse effects on said goggle system.

7. The night vision goggle system of claim 1 wherein said objective lens assembly comprises three cemented doublet lens components, having a focal length of about 26 mm and a relative aperture of f/1, and wherein said objective lens assembly is mounted for limited axial displacement by rotation within said housing over an 135°

arc so as to adjust the focus thereof over a predetermined range.

9. The night vision goggle system of claim 1 wherein said image intensifier tube includes an input fiber optic window formed with a concave input surface facing toward said objective lens assembly and having a radius of curvature R₈ and an output fiber optic formed with a concave output surface facing toward said collimator lens assembly and having a radius of curvature R₂₉.

12. The night vision goggle system of claim 1 wherein said collimator lens assembly comprises a first lens group of two cemented doublets having respective radii R₁₉ through R₂₄, vertex thicknesses t₁₃ through t₁₆ respectively, and refractive indices n₃₂ through n₄₃ respectively at three predetermined wavelengths, with an airspace d₁₀ reserved between said doublets, and a second lends group of two lenses consisting of a double convex lens having radii R₂₅ and R₂₆, a vertex thickness t₁₇ and refractive indices n₄₄ -n₄₆ at said three predetermined wavelengths, and of a double concave lens having radii R₂₇ and R₂₈, a vertex thickness t₁₈ and refractive indices n₄₇ -n₄₉, with an airspace d₁₂ reserved between said two lenses and an airspace d₁₁ reserved between said first and second lens groups.

14. The night vision goggle system of claim 9 wherein preferably R₈ is -28.957816 mm and R₂₉ is -14.388489 mm.

17. The night vision goggle system of claim 12 wherein the preferred characteristics of said collimator lens assembly are as follows:

space="preserve" listing-type="tabular">__________________________________________________________________________ Refractory Indices (n) Thickness at Wavelengths (λ

) Glass I.D. Radii and Spacing in Nanometers Lenses (Nos.) (mm) (mm) λ

.sub.1 (546 nm) λ

.sub.2 (480 nm) λ

.sub.3 (643 __________________________________________________________________________ nm) L.sub.13 575415 R.sub.19 = 36.321371 t.sub.13 = 4.600000 1.578300 1.585580 1.571550 R.sub.20 = -35.508841 L.sub.14 728284 R.sub.21 = 399.999996 t.sub.14 = 1.949400 1.734300 1.748050 1.722000 d.sub.10 = 0.475000 L.sub.15 607567 R.sub.22 = 21.462911 t.sub.15 = 6.500000 1.609940 1.615470 1.604650 R.sub.23 = -40.817992 L.sub.16 755276 R.sub.24 = 122.384040 t.sub.16 = 1.710000 1.761670 1.776370 1.748530 d.sub.11 = 11.600000 L.sub.17 620603 R.sub.25 = 23.317088 t.sub.17 = 5.100000 1.622860 1.628140 1.617770 R.sub.26 = -76.405867 d.sub.12 = 1.820000 L.sub.18 603380 R.sub.27 = -25.679215 t.sub.18 = 1.500000 1.607180 1.615560 1.599480 R.sub.28 = 67.006164 __________________________________________________________________________

8. A night vision goggle system comprising:

(a) a housing;

(b) an optical system accomodated within said housing, said system including a pair of eyepiece assemblies;

(c) each of said pair of eyepiece assemblies slidably mounted within said housing for individual adjustment of interpupillary distance;

(d) said optical system comprising an objective lens assembly, an image intensifier tube, and a collimator lens assembly, all mounted in optical axial alignement, and a splitter member mounted concentric with said optical axial alignment;

(e) said objective lens assembly three cemented doublet lens components, having a focal length of about 26 mm and a relative aperture of f/1;

(f) said three cemented doublet lens components include a first cemented doublet lens component having a convex surface on the object side with a radius of curvature R₁, an interfacial radius of curvature R₂, and a convex surface on the rear side with a radius of curvature R₃, vertex thickness t₁ and t₂ and respective refractive indices n₁ -n₆ at three respective wavelengths;

a second cemented doublet lens component having a front convex surface with a radius of curvature R₄, and interfacial radius of curvature R₅ and a plane rear surface P₁, vertex thickness t₃ and t₄, and refractive indices n₇ -n₁₂ and at said three respective wavelenghts;

a third cemented doublet lens component having a front convex surface with a radius of curvature R₆, an interfacial radius of curvature R₇ and a plane rear surface P₂, vertex thicknesses t₅ and t₆, and refractive indices n₁₃ -n₁₈ ;

with an airspace d₁ reserved between said first and second doublet lens components and an airspace d₂ reserved between said second and third doublet lens components.

13. The night vision goggle system of claim 8 wherein the preferred characteristics of said three cemented doublet lens components are as follows:

space="preserve" listing-type="tabular">__________________________________________________________________________ Refractory Indices (n) Thickness at Wavelengths (λ

) Glass I.D. Radii and Spacing in Nanometers;

Lenses Nos. (mm) (mm) λ

.sub.1 546 nm) λ

.sub.2 (706 nm) λ

.sub.3 (852 __________________________________________________________________________ nm) L.sub.1 533580 R.sub.1 = 39.129003 t.sub.1 = 7.999999 1.535340 1.528770 1.525420 R.sub.2 = -32.156408 L.sub.2 683445 R.sub.3 = -1000.000393 t.sub.2 = 1.564999 1.686370 1.675610 1.670420 d.sub.1 = 0.782499 L.sub.3 620635 R.sub.4 = 28.1682 t.sub.3 = 13.302490 1.622470 1.615480 1.611920 R.sub.5 = -31.546746 L.sub.4 706303 t.sub.4 = 6.259997 1.711350 1.695380 1.687980 d.sub.2 = 5.150000 L.sub.5 620635 R.sub.6 = 24.434965 t.sub.5 = 8.356000 1.622470 1.615480 1.611920 R.sub.7 = -15.239962 L.sub.6 706303 t.sub.6 = 5.659998 1.711350 1.695380 1.687980 __________________________________________________________________________

10. A night vision goggle system comprising:

(a) a housing;

(b) an optical system accommodated within said housing, said system including a pair of eyepiece assemblies;

(c) each of said pair of eyepiece assemblies slidably mounted within said housing for individual adjustment of interpupillary distance;

(d) means operatively associated with each of said pair of eyepiece assemblies for providing individual focusing thereto;

(e) each of said pair of eyepiece assemblies including a focusing subassembly, a replicated mirror and a second subassembly;

(f) said focusing subassembly comprising a first cemented doublet leans component having a convex surface on the eyeball side with a radius of curvature R₆, an interfacial radius of curvature R₁₀, and an convex surface on the distal side with a radius of curvature R₁₁, vertex thicknesses t₇ and t₈, and refractive indices n₁₉ -n₂₄ respectively at three predetermined wavelengths, and a second positive meniscus lens component having a convex surface with a radius of curvature R₁₂ and a concave surface with a radius of curvature R₁₃, a vertex thickness t₉ and refractive indices n₂₅, n₂₆ and n₂₇ at said three predetermined wavelengths, with an airspace d₅ reserved between said first and second lens components.

11. The night vision goggle system of claim 10 wherein said second subassembly comprises a first positive meniscus lens component having a concave surface with a radius of curvature R₁₄ and a convex surface with a radius of curvature R₁₅, a vertex thickness t₁₀ and refractive indices n₂₈, n₂₉ and n₃₀ at three predetermined wavelengths, and a second cemented doublet lens component having a convex surface with a radius of curvature R₁₆, an interfacial radius of curvature R₁₇, and a convex surface with a radius of curvature R₁₈, respective vertex thicknesses t₁₁ and t₁₂, and refractive indices n₃₁ -n₃₆ respectively at said three predetermined wavelengths, with an airspace d₈ reserved between said first and second lens components.

15. The night vision goggle system of claim 10 wherein the preferred characteristics of said focusing subassembly are as follows:

space="preserve" listing-type="tabular">__________________________________________________________________________ Refractory Indices (n) Thickness at Wavelengths (λ

) Glass I.D. Radii and Spacing in Nanometers;

Lenses Nos. (mm) (mm) λ

.sub.1 (546 nm) λ

.sub.2 (706 nm) λ

.sub.3 (852 __________________________________________________________________________ nm) d.sub.4 = 13.800000 L.sub.7 589613 R.sub.9 = 30.555809 t.sub.7 = 4.100000 1.591420 1.596350 1.586660 R.sub.10 = -10.947386 L.sub.8 755276 R.sub.11 = -26.213006 t.sub.8 = 0.980942 1.761670 1.776360 1.748530 d.sub.5 = 0.392380 L.sub.9 713538 R.sub.12 = 19.126310 t.sub.9 = 5.500000 1.716160 1.722980 1.709620 R.sub.13 = 55.321973 d.sub.6 = 12.453708 d.sub.7 = 14.000000 __________________________________________________________________________

16. The night vision goggle system of claim 11 wherein the preferred characteristics of said second subassembly are as follows:

space="preserve" listing-type="tabular">__________________________________________________________________________ Refractory Indices (n) Thickness at Wavelengths (λ

) Glass I.D. Radii and Spacing in Nanometers;

Lenses Nos. (mm) (mm) λ

.sub.1 (546 nm) λ

.sub.2 (706 nm) λ

.sub.3 (852 __________________________________________________________________________ nm) L.sub.10 607567 R.sub.14 = -26.213006 t.sub.10 = 3.000000 1.609940 1.615470 1.604650 R.sub.15 = -13.309553 d.sub.8 = 0.700000 L.sub.11 755276 R.sub.16 = 26.213006 t.sub.11 = 0.981000 1.761670 1.776360 1.748530 R.sub.17 = 10.947386 t.sub.12 = 4.100000 L.sub.12 589613 R.sub.18 = -30.555809 1.591420 1.596350 1.586660 __________________________________________________________________________