|  | H |
SECTION H — ELECTRICITY

|  | H01 |
BASIC ELECTRIC ELEMENTS

|  | H01 |
Note(s) Processes involving only a single technical art, e.g. drying, coating, for which provision exists elsewhere are classified in the relevant class for that art.

|  | H01S |
DEVICES USING STIMULATED EMISSION

|  | H01S |
Note(s) This sub-class includes devices for the generation or amplification, by using stimulated emission, of coherent electromagnetic waves or other forms of wave energy. Also included are such functions as modulating, demodulating, controlling, or stabilising such waves. [2]

|  | H01S 1/00 |
Masers, i.e. devices for generation, amplification, modulation, demodulation, or frequency-changing, using stimulated emission, of electromagnetic waves of wavelength longer than that of infra-red waves

|  | H01S 1/02 |
· | solid

|  | H01S 1/04 |
· | liquid

|  | H01S 1/06 |
· | gaseous

|  | H01S 3/00 |
Lasers, i.e. devices for generation, amplification, modulation, demodulation, or frequency-changing, using stimulated emission, of infra-red, visible, or ultra-violet waves

|  | H01S 3/02 |
· | Constructional details

|  | H01S 3/03 |
· · | of gas laser discharge tubes [2]

|  | H01S 3/04 |
· · | Cooling arrangements

|  | H01S 3/045 |
· · · | Cooling the active medium [2]

|  | H01S 3/05 |
· | Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium

|  | H01S 3/06 |
· · | Construction or shape of active medium

|  | H01S 3/07 |
· · · | consisting of a plurality of parts, e.g. segments, optical fibres [2]

|  | H01S 3/08 |
· · | Construction or shape of optical resonators or components thereof [2]

|  | H01S 3/081 |
· · · | comprising more than two reflectors [2]

|  | H01S 3/082 |
· · · · | defining a plurality of resonators, e.g. for mode selection [2]

|  | H01S 3/083 |
· · · · | Ring lasers (laser gyrometers Fulltext... Hierarchy... Expanded...G01C 19/64) [2]

|  | H01S 3/086 |
· · · | One or more reflectors having variable properties or positions for initial adjustment of the resonator (varying a parameter of the laser output during operation Fulltext... Hierarchy... Expanded...H01S 3/10; stabilisation of the laser output Fulltext... Hierarchy... Expanded...H01S 3/13) [2]

|  | H01S 3/09 |
· | Processes or apparatus for excitation, e.g. pumping

|  | H01S 3/091 |
· · | using optical pumping [2]

|  | H01S 3/092 |
· · · | by flash lamp [2]

|  | H01S 3/093 |
· · · · | focusing or directing the excitation energy into the active medium [2]

|  | H01S 3/094 |
· · · | by laser [2]

|  | H01S 3/095 |
· · | using chemical or thermal pumping [2]

|  | H01S 3/096 |
· · | by applying a potential to the electrodes of a semiconductor laser [2]

|  | H01S 3/097 |
· · | by gas discharge of a gas laser [2]

|  | H01S 3/098 |
· | Mode locking; Mode suppression (mode suppression using a plurality of resonators Fulltext... Hierarchy... Expanded...H01S 3/082) [2]

|  | H01S 3/10 |
· | Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating (mode locking Fulltext... Hierarchy... Expanded...H01S 3/098; controlling of light beams, frequency-changing, non-linear optics, optical logic elements, in general Fulltext... Hierarchy... Expanded...G02F) [2]

|  | H01S 3/101 |
· · | Lasers provided with means to change the location from which, or the direction in which, laser radiation is emitted (optical-mechanical scanning systems in general Fulltext... Hierarchy... Expanded...G02B 27/17; electro-, magneto-, or acousto-optical deflection Fulltext... Hierarchy... Expanded...G02F 1/29) [2]

|  | H01S 3/11 |
· · | in which the quality factor of the optical resonator is rapidly changed, i.e. giant-pulse technique

|  | H01S 3/111 |
· · · | using rotating reflectors [2]

|  | H01S 3/113 |
· · · | using bleachable or solarising media [2]

|  | H01S 3/13 |
· · | Stabilisation of laser output parameters, e.g. frequency, amplitude [2]

|  | H01S 3/14 |
· | characterised by the material used as the active medium

|  | H01S 3/16 |
· · | solid materials

|  | H01S 3/17 |
· · · | amorphous, e.g. glass [2]

|  | H01S 3/18 |
· · · | semi-conducting material

|  | H01S 3/19 |
· · · · | with PN junction [2]

|  | H01S 3/20 |
· · | liquids

|  | H01S 3/22 |
· · | gases

|  | H01S 3/223 |
· · · | polyatomic [2]

|  | H01S 3/23 |
· | Arrangements of two or more lasers not provided for in groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...H01S 3/02-H01S 3/22, e.g. tandem arrangements of separate active media [2]

|  | H01S 3/30 |
· | using scattering effects, e.g. stimulated Brillouin or Raman effects [2]

|  | H01S 4/00 |
Devices using stimulated emission of wave energy other than those covered by groups Fulltext... Hierarchy... Expanded...H01S 1/00 and Fulltext... Hierarchy... Expanded...H01S 3/00, e.g. phonon maser, gamma maser