An optical bench, also known as an optical rail, is a piece of scientific equipment used in demonstrations involving optics and laser light. Like the optical table, the optical bench supports light sources, lenses and mirrors. Optical benches are much smaller than optical tables, and their size is a detriment to experimental accuracy. Not appropriate for serious scientific research, optical benches are mainly used as a classroom demonstration tool. Optical benches are available for purchase from many online retailers specializing in scientific equipment.
Using an optical bench is in many ways similar to using an optical table. Each piece of equipment on the rail is held in place by a tightened screw. Loosening the screw allows the user to slide the mirror or light source along the rail. Any piece will come off the rail if the screw is completely loosened. The ease of assembly allows the user to quickly set up the bench.
Its design makes the optical bench inappropriate for conducting a reliable scientific experiment. A bench's small size and cheaper materials make it prone to picking up outside vibrations, a variable that could invalidate an experiment using laser light. Also, the bench is simply too small to hold the equipment necessary to perform an experiment. These drawbacks make the optical table a necessity. Its larger size and sturdier materials make it a solid, stable surface that can support multiple mirrors and prisms.
Unable to perform extensive experiments, the optical bench is a valuable tool for secondary school teachers or undergraduate professors demonstrating the principles of optics. In these situations, an optical bench's small size and ease of use is optimal. After a demonstration, students can use the bench themselves, gaining a deeper understanding and appreciation for optics. Unlike the powerful lasers found on most optical tables, those included in optical benches are low power and completely safe for classroom use.
Many scientific equipment suppliers offer optical bench sets. Price will generally increase with models that are longer and/or include more accessories. It is also an option for an educator to create a customized set by buying only the pieces he or she needs. If a piece should break during classroom use, most suppliers offer replacement parts at a reasonable price. Another benefit is that when dissembled, an optical bench takes up little space in the classroom.