USRE6343E - Improvement in lenses for head-lights - Google Patents

Description

H; c. FELTHOUSEN.

Lens for Head-Lights.

No, 6,343, ReissuedMarch 23 1815..

H l [I .1 i 53 a g W 'M ll| I w-Mr UNITED STATES PATENT OFFICE.

HENRY CaFELTHOUSENfOF BUFFALO, XIMV YORK.

IMPROVEMENT IN LENSES FOR HEAD-LIGHTS.

Specification forming partof Letters Patent No. 110,449, dated December 27, 1870 reissue No. 6,313, dated March 93, 1875 application filed J one 15, 1874.

To all whom 'it may concern:

Be it known that I, HENRY G. FELTHOUSEN, of the city of Buffalo, in the county of Eric and St-ate of New York, have invented an In proved Glass or Lens for Head -Lights, of which the following is a specification:

A ships head-light, which is required to be visible at different ranges or distances, and from different directions, owing to the various positions a vessel assumes, should be constructed in such a manner as to equally illumine a considerable arc of the horizon and at various a1titudes. \Vith ordinary head-lights the rays are unequally distributed over the illuminated arc, the intensity of the light being so much greater at the center as to render the light visible at a considerable distance only when the observer is near the center of the illuminated arc.

A front glass for head-lights has heretofore been used, composed of a series of hollow tubes filled with a liquid, and arranged vertically side by side, in the form of anal-0,001- responding to the curve of the front portion of the lantern wherein they are placed. .Each of these tubes operates as a lens to collect the lateral rays to a focus, from whence they are more equally dispersed over the required are of the horizon. Besides the labor and care required to properly fit and secure these tubes in place, and the liability of the tubes breaking from the expansion of the liquid therein,

these glasses are defective from the fact that' the rays, which strike the tubes near their line of junction, impinge at such an angle as to be reflected from the surface of the tubes,

instead of being transmitted, whereby a considerahle portion of the illuminating power of the light is wasted.

The object of my invention is'to produce a glass that shall possess the advantages re sultin g from the use of a series of refracting convex surfaces, joined together at theiredges, without the defects of the glass above described.

In the accor npanying drawin", Figure 1 is a horizontal section of a lantern provided with my improved glass. Fig. 2 is a front elevation thereof. I

Like letters of reference designate like parts in both of the figures.

A represents the case of the lantern of ordinary cylindrical form; B, the lamp; U, the reflector in the back; and l), the, glass shown in the drawings, with both concave and convex surfaces constructed alike.

These two surfaces of the glass, the inner and outer, produce corresponding effects, the one augmenting or duplicating the effect produced by the other, except that a few of the rays strike certain portions of the inner surface at such an angle as to be reflected. Either surface will produce the required effect of refractinggand dispersing the rays that pass through the central portion of the glass, so as to cause the light .to be more equally distributed over the illuminated arc of the hori zon.

in one piece, with convex ribs or collecting refractingsurfaces, substantially as and for the purposes herein shown and described. HENRY O. FELTIIOUSEX.

'itncsses:

J. J. Bonni EDWARD \Qn-saELn.

Although in the foregoing description I may

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