US942589A - Lamp. - Google Patents

Description

H. SALSBURY.

LAMP.

APPLICATION FILED DB0. 16, 1907.

942,589. Patented Dec. 7, 1909.

WWA/5.9659

HENRY sALsnURY, or LONDON, ENGLAND.

LAMP.

.application inea December 1e, 1907.

To all whom it may concern:

Be it known that I, HENRY SALSBURY, a subject of the King of Great Brita-in and lreland, and residingat 124k Long Acre, London, Ilngland, have invented `certain new and useful Improvements in and Relating to Lamps. of which the following is a specification.

My invention relates pecially applicable to such as are used in conjunction with motor vehicles.

As the beam of light projected from the lamps of a motor or other vehicle is generally of a more or less divergent character,

" any one approaching the vehicle from an opposite vdirection to that in which it is traveling, will enter the zone of light at a distance from the vehicle `depending on the character of the projected beam. When Athe intervening distance between the vehicle and the observer is short or the light is of great intensity, as for example when acetylene is used as the `illuminating agent, it is found that the eyes of the observer are so a'ected that he is unable to locate the exact position of the vehicle. This peculiar effect on the eyesight is termed glaring, and is very objectionable and dangerous when the vehicle concerned is traveling at a high speed anld is met. by an observer in another vehicle traveling in the opposite direction.

According to the. present invention, by providing suitable surfaces within the lens or glass of the lamp, the rays of light which would otherwise be projected upward and produce glaring in the eyes of any one ap preaching, are reflected downward and the main beam of light emitted from the lamp restricted to a level below that of the line ofvision of the observer.

My invention therefore has for its object to provide an improved lens or glass, which will prevent the objectionable effects of glaring especially noticeable in connection with acetylene lamps.

,My invention consists in a lens or glass of the solid or built up type, in which surfaces are formed for substantially preventing upward projection of the rays from the lamp within the limit in which the intensity of the light would be such as to produce glarlng.

My invention further consists in the improved lenses or glasses and lamp to be hereinafter described.

' :."erring now the accompanying draw- Spec'cation of Letters Patent.

. characters to lamps, and is es` Patented Bec.. "i, 190%?.

Serial No. 406,822.

ings which illustrate my invention and form part of my specification, and in which like ofreference indicate corresponding parts in both views, Figure l `shows a part sectional elevation of a lens constructed according to my invention, Fig. 2 showsv asectional elevation of a lamp illustrating the action of my 4improved lens or glass.

In carrying my invention into effect according to one form, l provide a lens or glass which is formed bycementing or otherwise assembling together in a mount a (Figs. l and 2), a number of horizontally disposed strips or laininae, Z), of glass or other translucent material. rl`he dimensions of the strips may of course, vary according to circumstances, in the example illustrated the dimensions being leg wide x if thick, rlhe strips or laminae are polished on their upper faces h and ground on their lower faces z', so that any rays vof light which strike obliquely against the upper faces of the laminas are to a great extent reflected downward, while those which strike against the lower faces are absorbed to a reat extent. The lens is then ground to any esired shape and mounted in a lamp, Fig. 2.

The burner, 0, is placed for example in the focus of a parabolic reflector,l d, which pro'ects the reflected light in a series of paralle rays, c, through the laminae, b, of the lens. rlhe direct light from the burner however is projected in a diver` ent beam, the upwardly inclined rays, f, of which are reflected downward by the upper surfaces of the laminee, while the downwardly inclined rays, g, are absorbed by the lower surfaces.

rlhe design of the lamp should be such, that any rays which may happen to be projected in an upward direction intercept the vision at a point where their ,intensi-ty is so much diminished as to produce no objectionable results. It will thus be seen that'practically only horizontal and downwardly inclined rays of light are emitted from the'lamp.

In some cases the upper surfaces of the laminae may be silvered while the lower surfaces ma be ground or coated with a light absorbing material, or may be ground and coated with a light absorbing material, while in other cases both the surfaces of the laminas may be ground.

By means of my invention it will be evident that the rays of light which -would otherwise issuein an upward direction, are

observers line of reflected downwardly or substantially horizontally by the upper surfaces of the laminas, the downwardly directed rays being whlly or partially-absorbed by the non-reflecting or y light absorbing surfaces on the lowery faces of`the'laminae. The objectionable ef` fect of glaring is thus entirely avoided, as any rays of light which may disperse in an upward direction are restricted to the zone in which their intensity is sufliciently diminished to produce no objectionable results.

Having now described my invention, what I'clairn as new and desire to secure by Letters Patent is I l. As an article of manufacture, a glassv formed of laminas having reflecting surfaces on one side `of said laminae and light absorbing surfaces on the other side of same.

2. As anl article of manufacture, a glass formed of laminae having a polished surface on one side of said laminas and a ground surface on the other side of same.

3. In combination, a source of light, a. plurality of translucent laminas disposed edgewise to the rays of light from said source, means disposed between the laminas for reflecting certainof the rays of light passing through said laminae, and means disposed between said laminas for absorbing certain other of said rays of light.-

4C. As an article of manufacture a glass having reflecting and light absorbing surfaces disposed edgewise to the light trans-l mitting surfaces of said glass. I

5. In combination a source of light, and a plurality of translucent laminas disposed 4 transversely tothe rays from said source, said laminas having reflecting surfaces on theiry upper sides yand light absorbing surfaces on their lower sides.

6. As an article of manufacture a glass having a plurality of parallel light absorbing surfaces disposed edgewise to the light transmitting .surfaces of said glass.

7. As a vnew article of manufacture, a glass having a plurality of light-absorbing surfaces disposed edgewise to the light transmitting surfaces of said glass.

In testimony whereof I have signed my nameto this specification in the presence of two subscribing witnesses` L HENRY SALSBURY.

lVitnesses:

ALBERT E. PARKER, FRANCIS J. BIGNELL.

Images