IL44645A

IL44645A - Method and system for illuminating a target

Info

Publication number: IL44645A
Application number: IL44645A
Authority: IL
Original assignee: Kms Fusion Inc
Priority date: 1973-05-21
Filing date: 1974-04-16
Publication date: 1976-09-30
Also published as: IT1012670B; ES426475A1; JPS5026999A; FR2231027B1; AU6810974A; BR7404130D0; IL44645A0; JPS5737836B2; NL7406231A; FR2231027A1; GB1459936A; BE815104A; DE2424714A1; ZA742434B; CA1020381A

Abstract

1459936 Optical apparatus K M S FUSION Inc 17 May 1974 [21 May 1973] 21953/74 Heading G2J A system for providing even illumination of a minute target located at or close to a point 42, comprises a mirror system formed by a pair of concave, ellipsoidal mirrors 34, 36 having a common focal point located at 42, each mirror having an aperture 38, 40 on a common axis through the focal point 42, together with a laser and associated system of mirrors which form laser beams 1, 2 which are directed along said common axis m opposite directions through the apertures 40, 38 respectively. The second focal point of each mirror is positioned adjacent the aperture in the other mirror, at the focus of a lens 26, 28. Each laser beam may pass through an aspheric corrector plate in front of the lens 26, 28. [GB1459936A]

Claims

CLAIMS;

1. The method of illuminating a target comprising the steps of providing bifocal reflective means having a first focus at said target and a second focus displaced therefrom on a system axis, directing a collimated beam of electromagnetic energy toward said target, and focusing said collimated beam at substantially said second focus coaxially with said system axis, whereby said focused beam is reflected by said reflective means over an opposing area of said target.

2. The method set forth in claim 1 wherein said focusing step comprises the steps of focusing paraxial rays of said collimated beam at said second focus, and focusing marginal rays of said collimated beam at substantially said second focus but between said first and second foci.

3. The method set forth in claim 1 or 2 for illuminating a thermonuclear fuel pellet at said target comprising the further step of positioning said reflective means with respect to said. target and focusing said collimated beam with respect to said second focus of said ■ reflective' means so 'as to achieve a preselected condition of target illumination at a predetermined phase of pellet implosion.

4. In an optical system for illuminating a target according to the method set forth in claim 1, and including means for directing a collimated beam of electromagnetic energy generally toward said target and means disposed on a system axis and adapted to focus said collimated beam over the surface area of said target from a direction substantially orthogonal to said surface, the improvement wherein said focusing means comprises bifocal reflective means disposed to have a first reflective focus at said target and a second reflective focus displaced therefrom on a system axis and means disposed in the path of said collimated beam to focus said beam at substantially said second focus of said reflective means, whereby said beam is incident from said second focus onto said reflective means and is reflected thereby onto a target surface area.

5. The improvement set forth in claim 4 further comprising means for focusing paraxial rays of said collimated beam at said second reflective focus and means for focusing marginal rays of said collimated beam at substantially said second focus but between said first and second foci„ 44045-2 Ψ

6. The improvement set forth in claim 4 for focusing over a surface area of said target first and second collimated beams of electromagnetic energy generally directed toward said target, wherein said focusing means comprises first and second opposed, centrally apertured bifocal reflective means coaxially disposed on said system axis, said first and second reflective means each having a first focus disposed at said target and a second focus disposed in proximity to the said central aperture in the opposing reflective means, and third and fourth means respectively disposed on said system axis externally of said first and second reflective means in the path of a corresponding collimated beam to focus each said collimated beam through a corresponding aperture in the adjacent reflective means to substantially the said second focus of the opposing reflective means .

7. The improvement set forth in claim 6 wherein said first and second reflective means respectively comprise first and second ellipsoidal reflectors. 44645-

8. .8. The improvement set forth in claim 6 or 7 wherein said first foci are in substantial coincidence at said target.

9. The improvement set forth in claim 6 or 7 wherein said first focus of said first reflective means is displaced from said first focus of said second reflective means at said target in a direction away from said second reflective means.

10. The improvement set forth in claim 9 for illuminating a spherical target wherein said first foci are disposed within said target and are separated by a distance less than the diameter of said target.

11. The improvement set forth in claim 6 or 7 wherein said collimated beams are directed along said system axis, and wherein said third and fourth means each comprise a focusing lens disposed to focus paraxial rays of an associated collimated beam to said second focus of the opposing reflective means. 44645

12. The improvement set forth in claim 6 or 7 wherein said third and fourth means each comprise means disposed to focus marginal rays of the corresponding collimated beam between said first and second foci of the opposing reflective means.

13. ■ 13. The improvement set forth in claim 6 or 7 wherein said third and fourth means each comprise means to focus paraxial rays of the corresponding collimated beam to said second focus of the opposing reflective means, and means to focus marginal rays of the corresponding collimated beam to substantially said second focus but between said second focus and said first focus of the opposing reflective means,

14. The improvement set forth in claim 13 wherein each said paraxial ray focusing means comprises a focusing lens.

15. The improvement set forth in claim 13 or 14 wherein each said marginal ray focusing means comprises an aspheric corrector plate.

16. The improvement set forth in any of the foregoing claims 6-15 for illuminating a thermonuclear fuel pellet at said target to achieve pellet implosion, wherein said first and second reflective means and said third and fourth focusing means are disposed with, respect to said target region to achieve a preselected condition of target illumination at a predetermined phase of pellet implosion.