A gas laser is provided in which either or both of two "plug-in" modules, one of which comprises the plasma chamber and the other of which comprises the associated high voltage components and circuitry, can be quickly and easily replaced by relatively unskilled personnel without any need for optical realignment. This feature makes it possible to use sealed plasma chambers even in applications where lasers are operated only intermittently and the sealed plasma chambers have limited operating life. With the elimination of the gas handling system, it becomes possible to manufacture compact, and in some important cases, portable and light weight lasers with replaceable plasma chambers and high voltage circuits. The invention is addressed to lasers operating at low to medium power output.
In a preferred embodiment, each high voltage electrode of the plasma chamber includes a connector plate that extends through the envelope and removably engages a support plate of the module containing the high voltage pulse circuitry. These support plates are precisely positioned with respect to two resonator mirrors mounted permanently on a base structure, while the connector plates are precisely positioned with respect to the electrodes and windows of the plasma chamber. The positioning of the connector plates with respect to the electrodes, the windows and the optical axis is identical for each of the interchangeable plasma chambers. The module containing the high voltage circuitry is releasably positioned on the base by two or more locator pins that retain it in a precise predetermined spatial and angular position with respect to the two mirrors. The position of this module with respect to the mirrors is identical for each of the interchangeable modules.
The plasma chamber module thus "plugs in" to the high voltage module which in turn "plugs in" to the base structure. Either or both of the modules are readily exchanged with any other similar modules without optical realignment. I -