Abstract: A copying-machine projection system successively projects successive strip-shaped zones of an original onto successive strip-shaped zones of a photosensitive surface. The projection system is of the type comprising at least one row of component projection objectives extending transverse to the direction of relative movement as between projection system and photosensitive surface. The individual component projection objectives are constituted by corresponding lenticular elements of plural lens bars, the lens bars extending transverse to the relative-movement direction and being provided with respective rows of lenticular elements. The projection system projects a strip-shaped image onto the photosensitive surface but also forms an intermediate image plane.

Abstract: A contact lens has a concave surface which is adapted to contact the cornea of an eye and a convex surface which is adapted to contact the eyelid. At least the convex surface of the lens possesses hydrophilic characteristics although the concave surface of the lens preferably possesses such characteristics also. In any event, the convex surface of the lens has a greater wettability than the concave surface thereof. The more highly hydrophilic character of the convex surface prevents the deposition thereon of fatty substances carried by the tear fluid which may cause opacity of the lens. The less highly hydrophilic character of the concave surface decreases the forces responsible for maintaining the lens in position in the eye, although not to such an extent that the lens does not remain properly positioned.

Abstract: A concave die punch of the type required in the formation of silicone elastomer contact lenses in which the curvature of the marginal zone is greater than the curvature of the central zone is made by making a convex die negative from glass or a vitreous ceramic; providing the negative with a thin metal coating, and then forcing a concave die positive made of a heat hardenable plastic in an enclosed space against the metal coated surface of the die negative while heating the said resin to harden it, thereby causing the metal coating to adhere to the positive and thus transferring the metal coating to the die positive whereby a reproduction of the surface of the die negative on the die positive is obtained.

Abstract: A method is disclosed which involves the production of shaped silicone elastomer-containing articles. In making an article of this type, a silicone elastomer-containing mass is formed to the desired configuration by subjecting it to pressure with a suitable die or pair of dies. Generally, the shaped mass will adhere to the die, or to one of the pair of dies, used for the shaping operation. A mechanical loosening of the shaped mass poses great difficulties. On the one hand, if sufficient caution is not excerised during loosening of the shaped mass, scratching or breakage of the latter will occur, particularly if the shaped mass is of small thickness. On the other hand, the exercise of great caution during loosening of the shaped mass is very time-consuming and, further, may still not yield satisfactory results if the shaped mass is of small thicnkess.

Abstract: A lens of a soft and readily damaged material is placed onto a support having a surface whose contour corresponds to the mating contour of the juxtaposed surface of the lens. The support is rotated and the lens is shifted on it until the lens is centered on the surface of the support, whereupon suction is applied through the support to the lens to hold it immovable as the marginal zones of the lens are being worked.

Abstract: An article composed of a silicon elastomer and which includes activated silicon dioxide as a filler is subjected to ion bombardment. The nature and energy of the ions are such that certain regions of the outer silicone elastomer layers of the articles are destroyed while, at the same time, the silicon dioxide filler is exposed at these regions. The nature and energy of the ions are also such that the remaining regions of the outer silicon elastomer layers of the article are transformed into activated silicon dioxide. As a result, the surface of the article becomes hydrophilic. The effects achieved are due to rupture of the silicon-oxygen and/or silicon-carbon bonds of the silicon elastomer during the ion bombardment, that is, the kinetic energy of the ions is sufficient to break these bonds. The ions used are activated gas ions formed by gaseous discharge and the ions generally have a kinetic energy between 3 and 50 electron volts. Preferably, oxygen ions are utilized for the ion bombardment.

Abstract: A lens of a soft and readily damaged material is placed onto a support having a surface whose contour corresponds to the mating contour of the juxtaposed surface of the lens. The support is rotated and the lens is shifted on it until the lens is centered on the surface of the support, whereupon suction is applied through the support to the lens to hold it immovable as the marginal zones of the lens are being worked.