A projection light valve system comprises a ring of light sources directed toward a parabolic reflector. The reflector reflects the light to a point of focus. An optical means, such as a lens, directs the light to a beam expander which expands the beam to irradiate a light valve. Multiple arrangements can be used to obtain a multicolor image.
A device for welding the ends of a tubular container made from plastic, in particular tubes has a holding device which holds the container in a stationary fashion with its open end facing in an upward direction and including means for warming a ring shaped peripheral region of the container proximate the opening to facilitate subsequent welding along an elongated seam travelling transverse to the longitudinal extension of the container. A mounting holds a plurality of diode lasers in an approximately circular manner such that their radiation is incident on the inner or outer wall of the container, either directly or via a deflection optics.
