Abstract: A pressure responsive potentiometer, including an elastic body which includes a silicone mass mixed with a carbon fraction in a quantity such that the electrical resistance across the body is changed when a force is applied to the body, which body has electrically conductive contact tabs or plates or like elements connected thereto in mutually spaced relationship. The invention is characterized in that the body (1) is composed of a mixture including a silicone mass, silicone oil and carbon grains, where the weight ratio of silicone mass to silicone oil is about 1:0.3 to 1:0.5, preferably about 1:0.4, and where the carbon grains have a size which is greater than a size corresponding to a 50 mesh sieve (50 meshes per inch) and a size which is smaller than the smallest dimension of the body (1).

Abstract: A dippable vehicle-headlamp, particularly a car headlamp, which is operative to transmit both ultra-violet and visible light and which includes a light source which is intended to emit both visible and ultra-violet light, a reflector and a filter. The reflector (1) and the light source (2) are intended to transmit simultaneously a light lobe which corresponds to a dipped-beam lobe and a full-beam lobe. The filter (4) is intended to filter-out visible light, but to transmit ultra-violet light. The invention is characterized in that the filter is mounted for displacement from a first position (FIG. 1) in which the filter (4) is located out of the beam path for transmission of the light lobe, to a second position (FIG.

Abstract: A vehicle headlamp comprises a reflector and a headlamp glass constructed to produce a so-called full beam lobe when a light source is located in a predetermined position in relation to the reflector. The invention is characterized in that the light source (11) is constructed to transmit both a large proportion of visible light and a large proportion of ultraviolet light, and in that a filter (19; 22; 23) is located in the beam path of the headlamp and is effective in filtering that part of the light emitted by the light source (11) which gives rise to a light lobe corresponding to the difference between a so-called full beam lobe and a so-called dipped beam lobe. The headlamp is further characterized in that the filter (19; 22; 23) is constructed firstly to filter light so that substantially no light within the visible light spectrum will be transmitted through the filter, and secondly to transmit ultraviolet light.