Abstract: Dental teaching and practicing apparatus for the simulation and practice of dental-clinical working or operating procedures, such as are generally employed for the education and training of dentists and their assistants. The apparatus which represents or incorporates a patient-simulator can be individually positioned, especially with consideration being given to limited space or place conditions, whereby during non-use thereof the apparatus can be brought into a space-saving stored position, and can also be set up in such a manner that within an unchanged assembly, it is comfortable for either a right-handed or left-handed person.

Abstract: An artificial denture-skull for dental teaching and practice purposes, consisting of a model of an upper jaw equipped with teeth and which is arranged on an upper support plate, and a model of a lower jaw equipped with teeth which is arranged on a lower support plate, and wherein both support plates on the inner surfaces facing the dentures for the mounting of the jaw models incorporate an O-ring seating arrangement for the jaw models, against which there can be clamped the jaw models through the application of their base surface with the interposition of a clamping device extending through the support plates and which can be manipulated from the outside. For the most possibly exact simulation of the human head, the denture-skull can be also connected with a cerebral cavity-defining skull portion, as well as with a pocket-shaped covering which includes a mouth opening for the formation of a complete phantom head.

Abstract: A mounting arrangement for a tooth in an artificial dental jaw model, especially in an artificial denture skull, and which is utilized for teaching and practice purposes. The tooth which is to be exchanged or replaced can be pulled out with an ordinary pair of extracting pliers and in an imitation of an actual extracting procedure, and the new tooth can be inserted with the application of a forcible or strong finger pressure.

Abstract: An artificial denture-skull for dental teaching and practice purposes, consisting of the model of an upper jaw which is equipped with teeth and of the model of a lower jaw which is equipped with teeth, the lower jaw model being connected with the upper jaw model for pivotal movement through the intermediary of two jaw linkages which are arranged at respectively both sides of the jaw models, whereby the lower jaw model is presently equipped with an articulated ball belonging to the jaw linkages and which is guided within an articulating track arranged in an articulating box on the upper jaw model. For the most possible exact simulation of the human head, the denture-skull can also be provided with a cerebral skull portion, as well as with a pocket-shaped covering possessing an oral or mouth aperture, for the resultant formation of a complete phantom head.

Abstract: An artificial denture-skull for dental teaching and practice purposes, consisting of a model of an upper jaw or maxilla equipped with teeth and with a model of a lower jaw or mandible equipped with teeth, the last of which is pivotally connected with the upper jaw model through two jaw linkages which are arranged at both sides of the jaw models whereby for fixing the denture-skull in an open position, a downwardly extending latching device is provided on the upper jaw model and which able to be brought into engagement with the lower jaw model. For the most possibly complete simulation of the human head, the denture-skull is also connectable with a cranial cavity-forming skull portion, as well as with a pocket-shaped covering which possesses an oral aperture.

Abstract: A honing device has a honing tool for the precision machining of blind-hole bores in a workpiece. The honing tool has a shank, at the free end of which honing strips are arranged. They can be moved radially outwards by means of a spreader rod. In a coolant duct system in the tool, during the machining of the workpiece coolant is supplied to the end of the honing tool facing the workpiece. To return the coolant, there are return ducts which extend along the outer periphery of the honing tool. The honing device also has a coolant feed device which can be aligned with and fixed to the honing tool. The feed and return of the coolant guarantee a precisely defined coolant circulation within the network zone.

Abstract: For determining the proper dose of therapy radiation for photocoagulation at the fundus of the eye, the fluorescent radiation excited by the therapy radiation (laser light) in the fundus of the eye is utilized. The fluorescence intensity passes through a characteristic minimum upon the termination of the coagulation process. Apparatus is disclosed for the detection by measurement of this effect. Optical beam splitters are provided to separate the fluorescent radiation from the therapy radiation. An electronically controlled shutter is provided for the passage and blocking off of the therapy radiation. The shutter is closed when the fluorescence intensity reaches a minimum after commencement of coagulation, or when the radiation reaches a predetermined amount, if this occurs before the fluorescence reaches its minimum.

Abstract: In a device for examining anterior sections of the eye, based on the Scheimpflug principle, an electric receiver is provided in the imaging-beam path for electronic evaluation of results of the examination. Various meridian sections in the patient's eye are produced by means of a rotatable prism. A fixation object and a graticule in the illumination beam path enable easy reproducibility of measurement results, as well as facilitating follow-up examinations which seek to observe the same eye for changes, from one examination to a later examination.

Abstract: A compact apparatus for the subjective and objective determination of refraction of the eyes of a person. Two projection ray paths (6, 7), separated in space from each other, are provided, both ray paths containing systems (10, 11) for the continuous adjustment of spherical and astigmatic effects. Together with an optical telesystem (15) and the lenses of the eye they focus a test mark (3) on the retina of each of the eyes (18, 20) of the test subject. The light reflected by the retina passes via mirrors (14) into observation ray paths (21). They focus the retina and thus the test mark (3) in an image plane (30). The adjustment systems are displaced until the images of the test mark appear sharp in the image plane (30). After such an objective determination it is possible by actuating the same adjustment elements (10, 11) to adjust subjectively until the test subject sees the test mark with optimum sharpness.

Abstract: In articulated optical systems, rotation of the image takes place due to the articulations. The invention eliminates this disadvantage by producing a signal whose polarity is dependent on the direction of rotation in which the image produced in the observation plane (64) is turned with respect to the object. By the signal, a compensation element (72) arranged in the articulated optical system is turned until the signal has disappeared. Two devices are disclosed for producing the signal: 1. At the start of the articulated optical system a mark (16) is introduced by reflection, it being focused at the end of the articulated optical system on a sensor (67). 2. On all articulations there are arranged position transmitters (111,112, etc.) which are connected with a minicomputer (130) which calculates the resultant image rotation and gives off a corresponding signal via a digital analog converter (131).

Abstract: A stereoscopic microscope arranged for multiple observation, so that a surgical operation or other event may be observed simultaneously by two observers, or by one observer and a television apparatus. Three observation light paths are provided, with the centers of their respective entrance pupils lying at the three corners of a triangle. By splitting one beam, two pairs of stereoscopically related observation paths can be obtained. The pupil of the split light path has a diameter which is larger than the diameter of the pupil the other two light paths by a factor approximately equal to square root of two, so that both observers will see images of approximately equal brightness with their right and left eyes. Various specific arrangements of the observation light paths are disclosed.

Abstract: A process for producing solutions of salts of water-soluble carboxylic acids of cationic dyes or optical brighteners, the solutions of cationic dye salts or brighteners salts which are obtained by this process and which are miscible with water in any proportion, and the use of these solutions for preparing dye liquors and printing pastes for dyeing, optical brightening and printing of, in particular, synthetic textile materials, which process comprises reacting the halide of a cationic dye or brighteners, in an aqueous or anhydrous medium, with at least one water-soluble carboxylic acid in the presence of an epoxide compound having a minimum of 13 carbon atoms.

Abstract: Apparatus for use with an operating microscope employed in observing the cornea of the human eye, for example in connection with cornea transplant operations. A plexiglass tube surrounds the objective of the microscope and is fed with light from a suitable source, so that an image of the circular illuminated lower end of the plexiglass tube is reflected by the cornea of the patient back into the microscope and is observed by the person using the microscope. The character and extent of distortion of the reflected image is an indication of the corneal astigmatism. The eyepiece of the microscope is provided with a reticle in connection with which the reflected image is observed. In one form of the invention, the recticle has diametrical crossed lines and concentric circular lines.

Abstract: The invention relates to a dispersion of a water-soluble basic dyestuff in an organic solvent that is at least partially miscible with water or in a mixture of such a solvent with water.

Abstract: In a brushless synchronous generator with an exciter, in which the three phase armature winding of the generator is coupled through a series regulator to the field winding of the exciter, and in which the rotating armature of the exciter feeds the rotating field winding for the synchronous generator through rectifiers, the series regulator being coupled in series between the three phase windings of the generator and the field winding of the exciter and including a control element, and in which there is a bypass diode across the exciter field winding, in order to protect the control element, a protective device is disposed between the control element and the three phase winding and an overvoltage arrester is placed in parallel across the exciter field winding and the bypass diode, the overvoltage arrester operating if an overvoltage occurs, thereby causing increased current to be drawn to actuate the protective device in series with the control element thereby preventing the synchronous generator from reaching

Abstract: A process for producing solutions of salts of lower aliphatic carboxylic acids of cationic dyestuffs which consists essentially of converting the halide, especially the chloride, of a cationic dyestuff into the salt of a lower aliphatic carboxylic acid by reacting the halide with the corresponding carboxylic acid in the presence of an epoxide compound having a maximum of 12 carbon atoms.

Abstract: A photocoagulator using a gas discharge lamp and a mirror for forming a double image of the luminous plasma region of the lamp in a photocoagulation area adjusted for size by interchangeable field stops is improved for easier adjustability when field stop sizes are changed. A manually operable screw ring moves the lamp axially relative to the mirror to adjust the separation of one image from the other relative to the size of the field stop, and the side of the field stop facing toward the coagulation area is illuminated for brightening the environment of the coagulation area for easier observation.