US3844638A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Beam doubler
Assignee: United States Department of the Navy
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Filing: 1973-10-18
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Granted: 1974-10-29
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Expires: 1993-10-18
Abstract
Abstract An optical beam-splitter having two triangular prisms cemented together to form another prism roughly cubical in shape. Looking at the roughly square end formed by two triangular ends of the prisms, the latter are cemented together along their hypotenuse sides, one hypotenuse side having a 50% reflecting-50% transmitting coating. The rear and lower sides of the device have a coating which provides total internal reflectance. The lower side is inclined upwardly from the position in which it would form 90* angles with the front and rear sides, the lower side being longer and the front side shorter than the corresponding sides of the other prism. A light beam is admitted thru the front side of the device and a pair of divergent beams leave the upper side which is at an angle of 90* to the front side.
Inventors
- 👤 P Lingenfelder
- 👤 J Fox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:00
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/10; G02B27/14; G02B27/144
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
224 words
A beam-splitting device for splitting an incoming beam of light into two outgoing light beams comprising: a front and a rear prism, each having their parallel-plane end faces in the form of a triangle, the triangle of the end faces of the rear prism being a right triangle and the triangle of the front prism being roughly a right triangle except that one of the two sides thereof which would form the right angle is inclined, said two prisms being fitted together along their hypotenuses so that the rear prism provides a rear and an upper side for the device and the front prism provies a front and a lower side, the lower side being the inclined side, one of the hypotenuses being coated with a partially reflecting-partially transmitting coating, the incoming light beam entering the front side and striking the reflecting-tRansmitting coating, part of the beam being reflected downward to the inclined side and being reflected upward thru the upper side of the device, and part of the incoming beam being transmitted to the rear side, reflected back to the reflecting-transmitting coating and reflected up thru the upper side of the device, so that two separated light beams emerge from said upper side, the angle of divergence of said light beams being the same as the angle of inclination of said lower side.
Claim 2
Dependent Claim
224 words
A beam-splitting device for splitting an incoming beam of light into two outgoing light beams comprising: a front and a rear prism, each having their parallel-plane end faces in the form of a triangle, the triangle of the end faces of the rear prism being a right triangle and the triangle of the front prism being roughly a right triangle except that one of the two sides thereof which would form the right angle is inclined, said two prisms being fitted together along their hypotenuses so that the rear prism provides a rear and an upper side for the device and the front prism provies a front and a lower side, the lower side being the inclined side, one of the hypotenuses being coated with a partially reflecting-partially transmitting coating, the incoming light beam entering the front side and striking the reflecting-tRansmitting coating, part of the beam being reflected downward to the inclined side and being reflected upward thru the upper side of the device, and part of the incoming beam being transmitted to the rear side, reflected back to the reflecting-transmitting coating and reflected up thru the upper side of the device, so that two separated light beams emerge from said upper side, the angle of divergence of said light beams being the same as the angle of inclination of said lower side.
Claim 3
Dependent Claim
12 words
The device of claim 1, wherein the angle of inclination is small.
Claim 4
Dependent Claim
13 words
The device of claim 1, wherein the upper and rear sides are equal.
Claim 5
Dependent Claim
13 words
The device of claim 1, wherein said beam splitting device is roughly cubical.
Claim 6
Dependent Claim
26 words
The device of claim 1, wherein the angles between the front and the upper sides and between the upper and the rear sides are right angles.
Claim 7
Dependent Claim
47 words
The device of claim 1, wherein the angle between the rear and lower sides is less than 90* by the amount of the angle of inclination and the angle between the front and lower sides is greater than 90* by the amount of the angle of inclination.
Claim 8
Dependent Claim
12 words
The device of claim 1, wherein said lower side is inclined upwardly.
Claim 9
Dependent Claim
18 words
The device of claim 1, wherein said coating on said hypotenuse is a 50% reflecting- 50% transmitting coating.
References Cited (Backward Citations)
US3677621A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-28 | 1978-04-29 | 1978-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-28 | 1982-04-29 | 1982-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-28 | 1986-04-29 | 1986-10-29 | $7700.00 | Window Closed / Lapsed |