Abstract: A vision testing system includes polarization spectacles having different polarization axes with or without .lambda./4 filters for the two polarization lenses forward of the eye of the patient to be tested. This system also includes a vision testing apparatus for generating light having a specific polarization direction. The vision testing apparatus includes essentially two polarization filters and two LCD-displays which are mounted alternately one behind the other. This arrangement can so influence the light coming from the light source that test figures or portions of the test figures can be seen by one eye or by both eyes. If a test figure is to be changed, then a corresponding command is issued via a key pad to a switching unit which drives two drive circuits of the two LCD-displays in a desired manner. By making appropriate modifications of the vision testing apparatus, a patient can be tested as to color-vision acuity.

Abstract: A safety spectacles against laser radiation has a first frame part which is of integral construction and in which shields are integrated, which cover the area between the frame and the spectacle-wearer's face. This frame part is also drawn over the spectacle-wearer's temple area and forms temple plates. Fitted pivotably to these temple plates are side arms which are each integrated in a further plate which forms the continuation of the associated temple plate.

Abstract: A method of producing a marking on a spectacle lens. For producing the marking, those regions on the surface of the spectacle lens which are to define the form of the marking are irradiated with an excimer laser through a mask which contains the marking in the form of a cutout.

Abstract: An arrangement for machining material by means of a laser beam includes a laser and an exit window mounted between the laser and the workpiece to be machined. The exit window is made of a highly-interlaced plastic to substantially prevent a contamination of the window by means of material splatterings during the machining operation. The highly-interlaced plastic has a high elasticity in microscopic regions. Such a window made, for example, from allyldiglocylcarbonate has a long service life which extends to several days in automatically operating equipment for spot welding with a laser beam.

Abstract: Laser safety eyeglasses include two protective filters for protecting the eyes against radiation from a laser. The eyeglasses include a frame having a main body defining two rims for accommodating the respective protective filters therein. Metal shielding plates are attached on the upper side of the frame as well as at the hinge ends of both mounting arms. The shielding plates stretch across the respective free regions between the frame and the face of the user. The mounting rims in which the protective filters are received as well as their connecting bridge are at least partially made of the same metal as the shielding plates.

Abstract: The invention is directed to an ophthalmic lens having a marking and a method of producing the same. The lens is suitable for spectacles and the like. The method includes applying a removable adhering substance to a region of the surface of the lens body so that the peripheral outline of the substance corresponds to the marking to be formed. Then, an anti-reflection coating is applied to the lens body and, at a time thereafter, the adhering substance and the portion of the coating covering the substance is removed thereby causing a recess to be formed in the coating having a peripheral outline defining the marking. The marking formed in this way is practically invisible to a person wearing spectacles equipped with the lens of the invention. On the other hand, the marking is clearly visible when viewed in reflected light.

Abstract: The invention concerns a method and apparatus for testing aspherical lenses, particularly continuous-focus eyeglass lenses. The negative picture (7) of a test pattern (1) is produced by means of a master lens (4) which is placed in the ray path of the optical system (6) of the testing device. (FIG. 1). Thereupon the negative picture is projected back onto the test pattern over said ray path, which is now traversed in the opposite direction. If the specimen to be tested is now substituted for the master lens, light edges appear in the plane of the test pattern and give information as to the deviations of the distribution of the refractive power of the test specimen from the desired values of the master lens.

Abstract: A device for rapidly demonstrating the darkening action of phototropic objects, particularly eyeglasses. The device has a housing or casing provided in its lower part (6) with a hollow space (7) which is placed over the objects to be demonstrated (8, 9) while such objects lie on any suitable horizontal supporting surface such as a table or desk. These objects are uniformly illuminated by a flash tube emitting light in the UV-A range and in the visible range. Upon each actuation of the circuit controlling the flash tube a plurality of flashes which succeed each other at a predetermined time interval is automatically given off.