DE3335468A1 - Spectacles of variable focus - Google Patents

Abstract

Two liquid chambers which are separated by a transparent diaphragm which can easily be buckled are formed in a manner enclosed by a front and a rear cover glass. Located in the ear bow of the spectacles are two longitudinal channels which in each case communicate from the front with one and the other liquid chamber. One channel contains a partial filling of mercury. When the head carrying the spectacles is inclined, this heavy mercury filling has the effect of shifting the ratio of the liquids of differing refractive power, and thus of displacing the film lens curvature and thereby changing the focus. <IMAGE>

Description

Glasses with varying focus

The invention makes it its task to provide glasses that resembles ordinary glasses in appearance and handling, but for different viewing distances changes the focus in a suitable manner Changes in focus are made while maintaining the full field of view.

The invention makes use of the known fact that the considerations at close range, usually with the head tilted downwards will.

For this purpose, these glasses have the optical on the one hand Properties of the usual glass lens and, on the other hand, @ those of a liquid lens.

Since no further control forces are to be used from the outside, it must be turned off the inclination of the head an actuating force can be derived.

For this purpose, the ear hook has a through-hole over its entire length, which communicates with the liquid lens e.g. by means of small hoses.

The front part of the ear hook hole is the optical one active liquid, in its rear part a mercury filling.

If the head is bent, the heavy mercury filling takes effect with a hydrostatic pressure increase ih the liquid lens, which is located under this Increase in pressure with increase in volume more vaulted.

Another embodiment provides that only Gla to the outside surfaces appear.

The liquid lens with its flexible walls is thus one Membrane that separates the two fluid spaces with the greatest possible refractive power difference separates, framed in a front and rear glass surface (or lens).

The two liquid spaces of the lens each have a connecting line that open once in front of and once behind the mercury filling in the ear hook.

This means that these glasses have a closed cable run, the is completely protected from environmental influences.

These glasses are best adapted to the respective viewing distance possible with the largest possible field of vision and the least need for care.

A possible exemplary embodiment is sketched in FIG. 1.

Between the glass surfaces 1 and 2 are the liquid spaces 3 and 4 enclosed, which are separated by the transparent membrane 11, the mercury filling 7 in the ear hook 8 moves the membrane 11 with the inclination of the head and thus changes the optical property in the desired way. The liquids are over the hoses 9 and 10 are routed and cannot mix, i.e. you strongly different refractive power is guaranteed.

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Claims (1)

Claims 10Glasses with varying focus, characterized in that the change in focus is produced by means of a liquid lens whose curvature is caused by Displacement of liquid by the action of the tilt of the head and the force of gravity a suitable displacement medium in the ear piece of these glasses. 20Glasses according to 1. characterized in that between a front and rear glass or a front and rear lens two fluid spaces with different Strongly refractive liquids are separated by an elastic transparent membrane are'der curvature in these spaces takes place in the manner described above. Glasses according to 1. and 2. characterized in that short-term for the purpose Focus activation an additional mechanical actuation is possible.