Filter glass

Filter glass can absorb light, UV rays and even heat. The most familiar example of this is in sunglasses, although filter glass is also used in industry in many gradations. Examples include the IR filter, which is used in operating theatres, or in video projectors to absorb heat from the powerful lamps. Further applications are found in colour filters for adjusting colour and light temperature, such as in airfield ground lighting or traffic lights.

Special raw materials

Filter glasses made with added phosphates offer the finest colour gradations. The colour variance and variety is much larger than with borosilicate glass, for example. This is because phosphates have a special effect on the colour-giving metal ions due to their structure, making the finest colour gradations possible. Phosphates from Budenheim are preferred in particular for manufacturing toned glass thanks to their excellent, flawless quality.