Lenses for holographic spectacles comprise an optically transparent base (1) on the interior surface of which, facing the wearer, a layer (2) of a recording material is applied, at least one three-dimensional hologram being recorded in the material. The layer (2) is made of a material transparent in the that spectral range, wherein the diffraction efficiency of the hologram is maximum. Located behind the hologram layer (2) (as viewed from the wearer's side) is at least one compensation layer (3) made of a selective absorbent having higher absorption of radiation in the aforementioned spectral range and maximum transmittance of radiation outside that range. To establish an integrated construction the mentioned elements of the lenses are joined together using lens cement. The invention significantly reduces three-dimensional modulation of the radiation passing through the lenses and resultant from the holographic image, thereby reducing color contrast over the lens aperture.

Die Erfindung betrifft eine Sehhilfe bei Netzhautablösung mit Beteiligung der Macula und ist gekennzeichnet durch eine Kreuzlinien-, Punkt- oder Ringrasterung der Gläser oder der Linsen, insbesondere eine solche mit einer Seitenlänge von unter 0,5 mm bei Kreuzlinienrasterung oder einem Abstand der Ringe von unter 0,5 mm oder einem Seitenabstand der Punkte von etwa 0,05 mm.

L'invention concerne un filtre holographique de protection contre des rayonnements, notamment laser.

Il comprend au moins un support (1) recouvert d'au moins deux hologrammes (2, 34). Les hologrammes sont fixés entre eux par une colle optique (33) associée à un absorbant sélectif.

Application : Lunettes ou visières anti-laser.

The method of the production of holographic lenses for the correction of faulty eye-sight requires two Laser beams emanating from the same source. One of them (the object beam) has to contain the whole of the object's information which the hologram, once made, has to reproduce.

These two beams are simultaneously projected on the photosensitive material on which the interaction pattern is recorded.

The final phase of the hologram's production is the chemical process which is similar to the photographic film development.

The production of the holographic lens requires an object beam which contains the information of the lens' function and not of its image.

The result of the above procedure is the creation of a lens suitable for ophthalmological use.

A moving picture of a scene is recorded with a relative lateral movement between the scene and the recording mechanism. The recording is played back and viewed through a light filter which has a greater optical density for one eye than for the other eye. One eye perceives a darker image which appears to lag in time the image perceived by the other eye. The three-dimensional effect can be controlled by controlling the direction and speed of relative movement, the relative optical densities of the filter used for each eye, and the size of and distance from the viewing screen. The invention also includes viewer glasses in which the optical density of one lens is at least 0.3 neutral density darker than the optical density of the other lens, and the difference in optical density between the two lenses is within the range of approximately 0.8 to approximately 2.0 neutral density.

A contact lens (1) has a transmission hologram (6) which provides diffractive power on a wavelength and/or amplitude selective basis whereby light from near and distant objects (N and F) can be focussed on the retina (5) of a presbyopic wearer. Similarly an implant lens can have a transmission hologram to correct for non-accommodative vision. The invention is particularly useful in providing an artificial eye lens with a bi-focal action without need for distinct near and far vision zones.