Abstract: A laser (1) has its laser head (3) connected to its base (2) by hinges having a common axis (R) parallel to the laser beam axis (4a). When the lamp for energizing the laser rod must be replaced, the head (3) can be pivoted about the axis (R) to a position in which the lamp can easily be removed from its cavity and a new lamp fitted therein, the removal and fitting being accomplished by moving the lamps along their axis (5a).

Abstract: A laser has a slab in which the beam F is propagated in zig-zag manner between two opposing faces which have the property of ensuring total reflection. For this purpose each of these faces is covered with a solid layer of a good heat conducting material and having a refractive index below that of the slab. Its thickness is preferably greater than three times the operating wavelength of the laser. Thus, a cooling fluid can be in contact with the solid layer to effectively cool the slab. Pumped energy sources are preferably provided opposite the layers.