
B–70114EN/04
E. GLOSSARYAPPENDIX
175
Name Meaning
Laser safety standard Standard to protect human bodies from hazards resulting from laser beams in
view of use of lasers and about laser products for sale
Linear
Polarization
Polarization in which a plain of polarization is at a constant angle with the axis
along which the light progresses
Maintenance Action taken by a user to preserve normal operation of a product, such as
adjustment or other measures specified in documents created by the
manufacturer for users
Maximum output Maximum radiation power or maximum radiation energy per pulse that a laser
product outputs in all directions where there is a hazard of exposure in view of
operational capacity in every area at any point of time after the production of
the laser product
Mode State of a resonant system in which an electromagnetic field has a specific
distribution
MPE Maximum permissible exposure Maximum laser radiation level that can be radiated onto human bodies without
harmful influence to them in an ordinary environment
Operation Laser product’s action covering all intended functions, not including mainte-
nance or service.
Optical resonator Device in which stimulated emission of light is used for a laser and which con-
sists of a pair of reflecting mirrors facing each other
Parameter Variable that is assigned a given value for a specific purpose and indicates
that purpose
Phase Amount representing a positional relationship between two adjacent highest
or lowest points on a wave
Power density Energy per unit area
Protective housing Laser product housing or its part designed to protect humans from exposure
to a laser beam exceeding an accessible emission level or strong collateral
radiation
Pulse duration Time interval between the points at which an instantaneous value on the lead-
ing and trailing edges is half the peak pulse amplitude
Pulse duty Ratio (%) of a duration in which a pulsating laser output is on, to its entire
cycle
Pulse frequency Repetition frequency at which pulsating laser beams are radiated from an os-
cillator
Pulse laser Laser that outputs energy in the form of a single pulse or a pulse train
Pulse output Laser output radiated in the form of a pulse train
Radian Measurement unit of angle; 1 radian equals 360°/2p
Radiant energy Energy emitted, transmitted, or received (measured in joules, or J)
Safety interlock Device combined with the protective housing of a laser product to stop its op-
eration automatically when part of the housing is removed
Semiconductor laser Laser that uses a semiconductor as an exciting medium