Optical table
An optical table is a device that is used to hold the elements of an optical system in a mechanically stable manner. Its plate is characterized by great rigidity . In contrast to an optical bench , an optical table does not have a preferred one-dimensional axis, but a preferred two-dimensional plane.
In many experiments in quantum optics , optical tables serve as a stable base on which the components of the structure are attached.
construction
An optical table consists of a rigid, usually rectangular plate that rests on a base. They are often stored using vibration dampers with a small spring constant . This serves to ensure that as little mechanical interference as possible, for example from impact sound or vibrations from road traffic, is transmitted to the optical structure.
In order to achieve great rigidity, the ratio of the thickness of the plate to the lateral expansion should be as large as possible. In order to still achieve an acceptable weight, the sandwich construction is used. The top and bottom of the table are formed by thick metal sheets. These sheets are connected by a large number of lightweight, vertical walls or tubes. In this way, it is not the thickness of the sheets that is decisive for the rigidity of the table, but the distance between the sheets. In addition, this construction is characterized by a high level of damping of vibrations with high frequencies. This is important so that the plate doesn't resonate like a bell for a long time.
Assembly
The top of optical tables is usually provided with a regular grid of threaded holes . This makes it possible, with the help of claws , to fasten the components of the structure in a mechanically stable but extremely flexible manner on the table. Another technique is to equip the components with magnetic feet . If it is foreseeable that the components will remain permanently in one place, bonding with two-component adhesive is also common.
The mounted elements are optical components, i.e. lenses , mirrors , prisms , etc. They are typically attached to stand-like mounting elements so that the beam path runs at a uniform height above the table surface.
To adjust the elements, their position must be made variable. There are mounting elements with the corresponding setting options, for tilting in two axes (for mirrors, see under plane mirrors ), for fine adjustment in the xy plane transverse to the beam direction (for lenses), for rotation perpendicular to the beam direction (of polarizers ), for rotation in the beam level (for prisms) or for height adjustment (of cuvettes with liquids). However, these are only the examples that occur particularly frequently; there are many other highly specialized versions.
Most of these adjustment options are operated by hand during the basic adjustment of the beam path. But some are also operated by ( servo ) motors in order to operate them frequently and / or in an automated manner.
Web links
- Optical table patent no.EP1413871B1 (accessed September 25, 2015)
- Linos table systems (accessed September 25, 2015)