DE8905130U1 - Liquid lens with continuously variable focal length - Google Patents

Description

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4 1989 · ·* ·· ·· ·· ··

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Dr.Or. Rudolf Weinzierl

Moststrasse 1 8510 Fürth

_1K liquid lens with continuously variable focal length,

The invention relates to a liquid lens (fluid lens)

2Q or a coupled system of such liquid lenses, which, due to their design, is capable of allowing large changes in focal length to be made very quickly.

This is achieved by the fact that in every liquid lens the rigid part, i.e. the ring-shaped hollow cylinder, is made of solid material such as metal or plastic, the flexible part, i.e. the cylinder after both open

2Q side bordering surfaces are made of transparent, highly elastic material such as acrylic or silicone membranes.
Such a membrane can also be made of transparent

OC are made of rigid material (glass) and already have a certain light-refracting effect through spherical, aspherical or cylindrical cut. One could think of computer glasses, which are in the

4Q basic concept is similar to normal distance glasses, but thanks to an additional elastic membrane with a cylinder jacket it becomes a liquid lens and can then be electronically automatically adjusted to any targeted distance.

The cavity between the cylinder and the two t membranes is filled with a glass-free, highly transparent

% 5 Liquid with high refractive index and low

Freezing point met.

'A Through an opening in the cylinder ring, the volume

% of the fluid in the lens easily using a

J| 10 coupled pressure cylinder with piston, which is filled with the || same fluid, to regulate.

% By changing the volume of liquid in the

M liquid lens changes the elastic membrane and

'-■ 15 takes on a spherical or aspherical shape depending on the construction.

In this way, the fluid-filled membrane cylinder, which is initially optically ineffective, changes from a diverging lens to a converging lens depending on the volume change between the membranes.

In a range of - 10 to + 10 diopters this can be achieved with minimal technical effort.

Another possibility of shifting the volume of liquid between the membranes in such a way that an optical effect is created by the change in shape of the membranes is that the membranes are surrounded by rigid materials in a ring-like manner, inserted into a cylindrical tube and the cavity between the membranes is filled with liquid.

When the spatial distance between the mounting rings in the tube changes, the membranes are changed (a-)spherically by pressure or tension and the liquid lens becomes optically active.

Another possibility is to make window-like openings in the rigid cylinder of the liquid lens, close them with elastic membranes and then attach

&igr; mechanical or electromagnetic pressure changes in

the capsule.

This method has the great advantage of being a closed system and can therefore be exchanged in an arrangement at any time without any special effort .

It is possible to arrange a finite number of such liquid lenses on the same optical axis in a tube one after the other and to use these liquid lenses individually

(J &igr; &ugr; G t, &eegr; &ugr;&ogr; r &eegr; .

üatH-i the possibilities are air - liquid lens - air liquid lens - air etc. as well as the combinations air - liquid lens - low refractive liquid liquidIli me - low refractive liquid - liquid-1i&eegr;Rπ etc. - air.

The main purpose of the invention is to help people with severe visual impairments, whose ability to see close up is impaired by

'.0 Circulatory and metabolic disorders are extremely variable and a practically impossible change in the refractive power of the reading glasses would be necessary to help by using liquid lenses in the form of magnifying glasses or liquid lenses fitted in pill frames, which are easy and precise to adjust but can quickly become accommodative mechanically or electromagnetically or even with electronic control.

A further aim of the invention is to use an appropriate choice of an optically clear, highly refractive liquid to make extremely thick and heavy spectacle lenses both in the collection and dispersion areas in

J5 to significantly reduce their thickness and weight. Another concern is the financial viability of visual aids for close-up vision for people whose values often change in a short period of time.

This problem can be remedied by using liquid lenses in spectacle frames, whose internal pressure and thus the refractive power can be easily changed even by non-optical people.

In a time when almost every workplace involves screen work, more and more insurmountable difficulties are arising with existing visual aids.

The screen glasses (60 cm) are too weak for reading the concepts, the loupe glasses (33 cm) are too strong for the screen.

Multifocal glasses are not suitable for long-term use due to the small facial features and the constant correction of the forced head position.

Something similar, or even worse, applies to the crystalline lens, where the clear viewing channel is very narrow and any lateral movement of the eyes leads to prismatic distortions of varying magnitude.

After prolonged screen activity, headaches occur.

The same applies to progressive lenses: a paradoxical forced head position for near distances.

The ideal pair of glasses would be one that has the cut of a normal pair of distance glasses on one side, but has a liquid lens on the other side that has to move within a maximum adjustment range of 3.5 diopters, so that when adjusted accordingly there are only minimal "emurrosis" distortions and liquid shifts. This liquid lens is controlled by a built-in micro-pressure receptor that automatically compensates for errors such as atmospheric pressure and temperature. Distance measurements determined by ultrasound or infrared receptors in the frame of the glasses are sent to the computer in the same way as the values of the pressure receptors. This computer determines in fractions of a second the pressure that is necessary under certain circumstances to adjust the liquid lens to a fixed distance.

9 · t ·

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This means that the fully automatic accommodation process, which is carried out by the lens in conjunction with the brain in the young human eye, is also guaranteed in the presbyopic eye as a connection between the liquid lens and the brain. A good deal of quality of life is thus returned to the working life of the aging computer worker.

The costs for such fully automatic glasses will, after an appropriate development phase, certainly be lower than those of a considerably more complex optical system.

The fall in prices in the area of small electronic computers is well known.

17.4.1909 ·;

Dr.Dr. R. Weinzierl

Reference symbols

1 Cylinder ring 2 Membrane(s) 3 Ring settings 4 Electromagnets 5 Tube 6 Window membranes 7 Pressure cylinder 8th Pressure piston 9 liquid 10 Pressure receptor 11 Valve(s)

Claims (9)

17.4.1989 .: .·' ."::" 14.6.1989 : : : G Bb 05 130.0 - 1" - Dr.Dr.Rudolf Weinzierl Moststrssse 1 8510 Fürth qnSprüche 1. Optical liquid lens for use as a _converging and diverging lens with a wide range of continuously adjustable focal length characterized, that the lens consists of a cylindrical rigid _shell made of materials such as metal or plastic, as well as one or two transparent, fully elastic membranes made of materials such as acrylic or silicone, and that the cavity between the membranes and the _cylindrical shell is filled with a crystal-clear liquid whose refractive index is in any case higher than that of the medium outside both membranes - normally: air. 2. Optical liquid lens according to claim 1 characterized, that the change in the volume of fluid within both membranes and thus the change in the refractive power of the lens via one or more valves by a Liquid-filled cylinder sliding piston. (Figure 1) 3. Optical liquid lens according to claim 1 characterized, _1Q that the two membranes are rigidly held concentrically at the edges and are mechanically or electromagnetically brought closer to each other in a tube filled with liquid or ,c from each other, whereby in the first case a converging lens is created, in the second case a diverging lens. (Figure Z). A change in the ärnwsits is stepless 2Q possible. 4. Optical liquid lens according to claims 1, 2 and 3 characterized, pe that in addition to the liquid chamber with its optical effect, which is delimited by the cylinder jacket and the two membranes, there are also additional elastic elements in the cylinder jacket like windows, through which pressure changes are transmitted mechanically or electromagnetically from the outside into the capsule. (Figure 3) 2g 5. Optical liquid lens according to claim 1,2,3 and characterized, that in a hollow cylinder (tube) several of these liquid lenses, each individually controllable 4Q bar, connected in series on the same optical axis, thus significantly improving the variation possibilities of conventional lens systems. Il It I > » · I II (I I (I It*· * t I I I · ♦♦ · \i 6. Optical liquid lens according to claim 5 &iacgr;&iacgr; 5 characterized by that the individual liquid lenses can be separated from one another not only by a gaseous medium such as air, but also by liquid transparent media ^with a low refractive index. 7. Optical liquid lens according to claim 1,2,3,4,5 and characterized in that all liquids used are very deep freezing points and at the same time relatively high boiling points. 8. Optical liquid lens according to claim 1,2,3,4,5,6 and characterized, that the membranes have an aspherical thickness design.
25 9. Optical liquid lens according to claim 1 characterized, that both membranes are made of transparent, rigid material (glass) and the cavity enclosed by the cylinder ring and membranes is filled with an extremely highly refractive liquid, which results in a significant reduction in the thickness and weight of a conventional lens. 40