摘要:
Described is a spectacle lens comprising a region (distance portion) designed for viewing at large distances and in particular nullto infinitynull, a region (near portion) designed for viewing at short distances and in particular nullreading distancesnull, and a progressive zone disposed between the distance portion and the near portion, in which the power of the spectacle lens increases from a value at a distance reference point located in the distance portion to a value at the near reference point located in the near portion along a curve (principal line) veering towards the nose. The invention is distinct in that the astigmatic deviation, i.e. the difference between the prescribed and the actual astigmatism along circles having a center lying 4 mm below the centration point and having a diameter of 10 to 40 mm satisfies the following conditions: two local minima occur which on a nullright-hand side spectacle lensnull are located at 95nullnull10null (according to TABO) and at 280nullnull10null, and on a nullleft-hand side spectacle lensnull at 85nullnull10null and 260nullnull10null; and two local maxima occur which on both a nullright-hand side spectacle lensnull and also a nullleft-hand-side spectacle lensnull are located at 215nullnull10null and 335null null10null.
摘要:
An ophthalmic lens in which one surface is provided with at least one region, in which the refracting power is practically constant except for aspherical corrections, and at least one transition region which is adjacent to the region having practically constant surface refracting power, and in which the surface refracting power increases or decreases continuously, and the other surface is provided with an astigmatic effect. The orientation of the surface having an astigmatic effect relative to the surface having continuous refracting power change is dependent on the position of the axis of the astigmatism of the eye. The surface having an astigmatic effect deviates from the toric shape and is independent of the orientation of the surface relative to the surface having continuous refracting power change which is a surface optimized for the axial position of 0.degree..
摘要:
A photochromic compound, in particular, for tinting optical elements made of a plastic material has reduced mobility in plastic material. The photochromic compound is a photochromic 2H-pyran and is distinguished by the aromatic residues being chemically rigidly attached in the 2-position to a spiropyran.
摘要:
Disclosed are adamantaneospiroheteroaromaticpyrans and adamantanospiro (1.3)oxazines of the general formula ##STR1## whereby R.sub.0 is a substituent from the series H, halogen, O-alkyl, N-alkyl,R.sub.1 -R.sub.4 : is a substituent from the series H, alkyl, aryl, subst. phenyl, naphthyl, heteroaryl, OH, alkoxy (C.sub.1 -C.sub.4), halogen, alkylamino, dialkylamino, cyan and trifluormethyl, orR.sub.1 and R.sub.2 or R.sub.3 and R.sub.4 or R.sub.2 and R.sub.3 are constituents of a condensed aromatic or heteroaromatic ring or an alkane ring with 4-8 C-atoms.
摘要:
An optically transparent photochromic plastic material is described which is comprised of materials with a sulphur content and which via polymerization processes contains photochromic organic compounds as solid ingredients, which possess at least two ring systems linked via carbon atom and whose photochromic tint is based on a reversible bond rupture to the spiro-C atom.
摘要:
Disclosed is a photochrome compound having a spirooxazine structure in a, as such known manner.In accordance with the present invention conjugated diazole-napthoxazine or oxazole-, thiazole, benzoxazole-or benzthiazole systems are added to the basic structure.Improved absorption in the wavelength range .alpha. than 350 nm as well as improved migration properties are yielded by this means.
摘要:
A progressive power ophthalmic lens having a convex front surface and a concave inner surface, of which at least one surface contributes to an increase in refractive power from a portion suited for distant vision via a progression zone to a portion suited for near vision along a plane or curved main meridian, along which the overall astigmatism is .ltoreq.0.5 dpt.The invented opthalmic lens is distinguished in that in order to form further channels of vision, the at least one surface contributing to increasing the refractive power is provided with at least one additional line which does not intersect the main meridian and runs from the distant portion to the bottom edge of the ophthalmic lens and on which the surface astigmatism has a minimum local value.
摘要:
An arrangement for determining the surface structure and especially the roughness of a specimen which includes an image lens system that focuses a parallel ray onto the surface to be examined with an inclined incidence direction and a lens system which reproduces the reflected light beam on a detector array. The distance of the detector array is approximately equal to the focal distance of the lens system. The distance of the surface from the lens systems is also approximately equal to the focal distance of the lens systems. The arrangement according to the invention offers the advantage that also with an areal specimen illumination as well as with greater changes of the distance between the arrangement and the surface to be examined, an unequivocal coordination exists between the angle, under which the light is reflected, and the individual detector elements.
摘要:
A pad assembly for eyeglass frames, in which an insert with a mounting portion is molded-in into the nose pad, whereby the mounting opening of the mounting portion is located outside of the nose pad; a connecting area is provided at the pad arm end which includes one or several projections and is adapted to be inserted into the mounting opening. The mounting opening is dimensionally reduced by plastic deformation of the mounting portion to such an extent that with an inserted connecting area of the pad arm end, a form-locking connection will result between the mounting portion and the pad arm.