Abstract: A projection exposure apparatus for microlithography has a light source, an illumination system, a mask-positioning system and a projection lens. The latter has a system aperture plane and an image plane and contains at least one lens that is made of a material which has a birefringence dependent on the transmission angle. The exposure apparatus further has an optical element, which has a position-dependent polarization-rotating effect or a position-dependent birefringence. This element, which is provided close to a pupil plane of the projection exposure apparatus, compensates at least partially for the birefringent effects produced in the image plane by the at least one lens.

Abstract: An objective for a microlithography projection system has at least one fluoride crystal lens. The effects of birefringence, which are detrimental to the image quality, are reduced if the lens axis of the crystal lens is oriented substantially perpendicular to the {100}-planes or {100}-equivalent crystallographic planes of the fluoride crystal. If two or more fluoride crystal lenses are used, they should have lens axes oriented in the (100)-, (111)-, or (110)-direction of the crystallographic structure, and they should be oriented at rotated positions relative to each other. The birefringence-related effects are further reduced by using groups of mutually rotated (100)-lenses in combination with groups of mutually rotated (111)- or (110)-lenses. A further improvement is also achieved by applying a compensation coating to at least one optical element of the objective.

Abstract: A projection exposure apparatus for microlithography has a light source, an illumination system, a mask-positioning system and a projection lens. The latter has a system aperture plane and an image plane and contains at least one lens that is made of a material which has a birefringence dependent on the transmission angle. The exposure apparatus further has an optical element, which has a position-dependent polarization-rotating effect or a position-dependent birefringence. This element, which is provided close to a pupil plane of the projection exposure apparatus, compensates at least partially for the birefringent effects produced in the image plane by the at least one lens.

Abstract: A method of adjusting a projection objective permits the projection objective to be adjusted between an immersion configuration and a dry configuration with few interventions in the system, and therefore to be used optionally as an immersion objective or as a dry objective. The projection objective has a multiplicity of optical elements which are arranged along an optical axis of the projection objective, the optical elements comprising a first group of optical elements following the object plane and a last optical element following the first group, arranged next to the image plane and defining an exit surface of the projection objective which is arranged at a working distance from the image plane. The last optical element is substantially without refracting power and has no curvature or only slight curvature.

Abstract: An objective for a microlithography projection system has at least one fluoride crystal lens. The effects of birefringence, which are detrimental to the image quality, are reduced if the lens axis of the crystal lens is oriented substantially perpendicular to the {100}-planes or {100}-equivalent crystallographic planes of the fluoride crystal. If two or more fluoride crystal lenses are used, they should have lens axes oriented in the (100)-, (111)-, or (110)-direction of the crystallographic structure, and they should be oriented at rotated positions relative to each other. The birefringence-related effects are further reduced by using groups of mutually rotated (100)-lenses in combination with groups of mutually rotated (111)- or (110)-lenses. A further improvement is also achieved by applying a compensation coating to at least one optical element of the objective.

Abstract: Mirror substrate consisting of crystal, especially silicon crystal, on which an amorphous layer, especially a quartz glass layer, is applied.

Abstract: Mirror substrate of crystal, especially silicon crystal, on which an amorphous layer, especially a quartz glass layer, is applied.

Abstract: An optical system with at least one optical element that causes a disturbance of the distribution of polarization over the cross section of a light beam wherein at least one birefringent optical element is provided, with a thickness which varies irregularly over the cross section, such that the disturbance of the distribution of polarization is at least partially compensated.

Abstract: The invention relates to a vacuum pump (1) with an oil separator (42) connected downstream of its outlet (33) and with a duct (45, 46) through which the oil separated in the oil separator (42) is returned to the vacuum pump (1); to feed back the oil in a simple manner, the oil feed duct (45, 46) opens into a duct (47) that supplies gas ballast to the pump (1).

Abstract: A system for measuring a plurality of parameters comprises a master processor and a multiplicity of slave processors. The master processor operates in time slices of 2 ms. Communication with the slave processors is performed in fixed format. The master processor manages the communications in certain time slices according to a matrix wherein each item or column represents a certain time slice. The items or columns in this matrix are organized such that the communications with those slave processors preceding the communication with a specific slave processor are the same as in all other items or columns containing a communication with said specific slave processor. In particular, the slave processors requiring short-intervallic timing signals are entered on top of the items or columns, whereas slave processors with longer-intervallic timing signals are entered below these.This system and the method of communication are particularly useful in a configurable medical monitoring system.

Abstract: A two-stage rotary vane vacuum pump includes a pre-vacuum stage having a pre-vacuum pumping chamber and an outlet valve; a main oil sump; and a first oil conduit having a first opening communicating with the main oil sump and a second opening communicating with the pre-vacuum pumping chamber. The first opening is located at a level below an operational oil level in the main oil sump. There is further provided an intermediate oil sump situated at a level above the outlet valve and being arranged for receiving oil from the pre-vacuum pumping chamber; and a second oil conduit leading from the intermediate oil sump to components of the vacuum pump to be supplied with oil. All such components are situated at a level below the intermediate oil sump.

Abstract: The invention relates to a method of making a pump ring for a two-stage vacuum pump (1) with a one-piece rotor system (14) having three sections (14a, b, c), whose end sections (14a and 14c form the two pumping stages and whose middle section (14b) forms an intermediate bearing, the diameters of the bearing section (14band of the rotor section (14a) forming the forepumping stage being equal. To reduce the tolerances that occur it is proposed that two bores be made in a single set-up from one end of a substantially cylindrical workpiece, the one forming the anchor contact (51) of the forepumping stage as well as the bearing bore (12) and the other forming the anchor contact (52) of the high-vacuum stage, and that before or after these bores aremade, additional bores (11, 13) are made in order to form the pump chambers (21, 17).

Abstract: A vacuum pump includes a first pump housing defining a pumping chamber; a pump rotor received in the pumping chamber; a drive motor operatively connected to the pump rotor; an oil casing receiving the first pump housing; and a second pump housing surrounding the first pump housing and the drive motor.

Abstract: In a system comprising a plurality of digitally addressable electronic devices, all devices have the same construction and are designed for being connected in series to a common central monitoring station. The addressing of these devices is accomplished by a plurality of address lines which are connected to input contacts of the respective device. Within each device, a selection gate is connected to the input contacts which provides an enabling signal if the signal on said address lines has a predetermined bit pattern. Each device has output contacts connected to its input contacts to which the input contacts of a next device are connected. The address lines are connected from the input contacts to the output contacts of the device in such a way that the contacts are interchanged, and an inverter is inserted in one of said lines so that the bit pattern forming the address provided at the output contacts is different from the bit pattern received at the input contacts.

Abstract: A high-vacuum pump includes a plurality of pump stages, each of which has a rotor and a stator. In one of the pump stages, either the rotor or the stator is provided with a structure that effects the gas conveying includes radially extending webs whose pitch and width decrease from the suction side of the pump stage to the thrust side of the pump stage.

Abstract: Rotating unit including a shaft, a blower rotor, and a motor armature is removable as a unit from the motor housing. The diameter of a first resiliently mounted bearing holder toward the blower rotor is larger than the diameter of the armature, which in turn is larger than the diameter of a second resiliently mounted bearing holder remote from the blower rotor.

Abstract: A lubricating system for supplying oil to the bearings of a shaft having a central oil pumping passage open at one end. An oil delivery tube reaches into the oil pumping passage. To achieve a positive transfer of the oil from the oil delivery tube to the inner wall of the oil pumping passage, means are associated with the upper end of the oil delivery tube for bringing the oil onto the inner wall of the oil pumping passage.