Abstract: A high-aperture wide-angle lens for digital image acquisition, comprising five lens elements, as viewed from the object side, i.e. from the left, a first, negative meniscus lens element, a second, positive lens element, a third, positive lens element, a fourth, negative lens element and a fifth, positive meniscus lens element. A diaphragm is arranged between the second lens element and the third lens element. At least three surfaces upstream of the diaphragm and three surfaces downstream of the diaphragm are embodied as aspherical surface. However, further surfaces can also have an aspherical design. On account of its extremely compact design and its outstanding optical properties, the proposed high-aperture wide-angle lens is suitable as an interchangeable lens for so-called “hybrid cameras”.

Abstract: A system for stereoscopic cinema projection comprising at least one projector for projecting two images, one image for a first eye and one image for a second eye of a viewer, is proposed. The beam paths of the light emerging from the projector respectively run through a linear polarizer to a correspondingly assigned projection lens. After passing through the projection lens, the beam paths of the two images, which are different for the eyes of a viewer, run through a radial and respectively a tangential polarization filter and are simultaneously projected, with different polarization states, exactly one on top of the other onto a metallic projection wall. By means of a visual aid for both eyes of a viewer, the lenses of which are configured differently for each eye with a radial and respectively a tangential polarization filter, each partial image is made visible only for the first or left eye or the second or right eye (or vice versa) and the 3D impression is thus generated for the viewer.

Abstract: A projection lens with a short focal length and high initial aperture is proposed. Such projection lenses are used, for example, in cinema projection. The projection lens is configured such that the sum of the overall length and the back focus (12) is between 2.8 times and 4.5 times the total focal length f?. The entrance pupil is at a distance of between 100 mm and 300 mm from the last lens surface (62; 150), which faces the illuminating mirror. The minimum stop number k of the projection lens is 1.7, and the projection lens is therefore also suitable for illuminating mirrors with a high aperture angle (of up to 17°).

Abstract: A projection lens with a short focal length and high initial aperture is proposed. Such projection lenses are used, for example, in cinema projection. The projection lens is configured such that the sum of the overall length and the back focus (12) is between 2.8 times and 4.5 times the total focal length f?. The entrance pupil is at a distance of between 100 mm and 300 mm from the last lens surface (62; 150), which faces the illuminating mirror. The minimum stop number k of the projection lens is 1.7, and the projection lens is therefore also suitable for illuminating mirrors with a high aperture angle (of up to 17°).