N3 Licence Test Questions With Complete Solutions
_____ into _____ laser beam should be avoided at all times, and
equal care should be exerted to avoid looking at _______ of the
beam, including those from ______. Correct Answers Looking;
primary; specula reflections; lens surfaces
_____ lasers are capable of emitting visible and/or invisible
laser radiation with the maximum accessible emission levels as
specified. As for visible Class 3a laser devices, they operate in a
_____ range of _______, which have an irradiance in the
emergent beam of not more than 25 W/m2. Correct Answers
Class 3a; power; 1 -5 mW
______ designed to filter out specific frequencies characteristic
of the system affords protection, but it may only be ______.
Correct Answers Safety eyewear; partial
_______ is seldom of concern except in dealing with very high-
powered lasers. But with ever increasing laser intensities
encountered, skin damage is becoming a concern. Correct
Answers Injury to skin
________ should be attached to laser equipment in a
conspicuous location indicating the ________ associated with
laser. Correct Answers warning sign; potential eye hazard
A light wave is then emitted when an ____ falls from the ____
energy state to a _____ energy state. Correct Answers excited
atom; excited; lower
, Avoid aiming laser with _____ and prevent looking along the
____ of the beam, which increases the hazard from reflections.
Correct Answers eye; axis
Basically, a laser system consists of two accurately ____
reflecting _____ between which the_______ is placed, one plate
being slightly _______. Correct Answers parallel; end-plates;
active lasing material; transparent
Binoculars or aiming telescopes should ___ be used to view
direct beam or reflected beam from mirrors unless the beam
intensities are _____. If necessary, a ____ having _______
should be placed in the optical path of telescope for such
situations or adequate _______ is worn by the operator. Correct
Answers not; greatly below the safe levels; filter; sufficient
optical density; laser protective eye wear
Class ____ laser systems are safe by virtue of their power output
or engineering design. These lasers ______ be considered as
hazardous even if all of the accessible laser radiation output is to
_____ to the eye's pupil or ______ into one mm spot on the skin
for ______. These lasers are considered as non-risk lasers, or
exempt lasers. The wavelengths could range from ultraviolet,
visible to infrared region. Class I continuous visible laser should
not have the accessible laser output of _____________. Correct
Answers 1; cannot; direct; focuse; a day; more than 0.39
microwatts
Class 2 laser systems are those emitting visible laser radiation,
in the wavelength range from 400 nm to 700 nm, in pulse or
continuous wave. This is a class of low-power and low-risk
_____ into _____ laser beam should be avoided at all times, and
equal care should be exerted to avoid looking at _______ of the
beam, including those from ______. Correct Answers Looking;
primary; specula reflections; lens surfaces
_____ lasers are capable of emitting visible and/or invisible
laser radiation with the maximum accessible emission levels as
specified. As for visible Class 3a laser devices, they operate in a
_____ range of _______, which have an irradiance in the
emergent beam of not more than 25 W/m2. Correct Answers
Class 3a; power; 1 -5 mW
______ designed to filter out specific frequencies characteristic
of the system affords protection, but it may only be ______.
Correct Answers Safety eyewear; partial
_______ is seldom of concern except in dealing with very high-
powered lasers. But with ever increasing laser intensities
encountered, skin damage is becoming a concern. Correct
Answers Injury to skin
________ should be attached to laser equipment in a
conspicuous location indicating the ________ associated with
laser. Correct Answers warning sign; potential eye hazard
A light wave is then emitted when an ____ falls from the ____
energy state to a _____ energy state. Correct Answers excited
atom; excited; lower
, Avoid aiming laser with _____ and prevent looking along the
____ of the beam, which increases the hazard from reflections.
Correct Answers eye; axis
Basically, a laser system consists of two accurately ____
reflecting _____ between which the_______ is placed, one plate
being slightly _______. Correct Answers parallel; end-plates;
active lasing material; transparent
Binoculars or aiming telescopes should ___ be used to view
direct beam or reflected beam from mirrors unless the beam
intensities are _____. If necessary, a ____ having _______
should be placed in the optical path of telescope for such
situations or adequate _______ is worn by the operator. Correct
Answers not; greatly below the safe levels; filter; sufficient
optical density; laser protective eye wear
Class ____ laser systems are safe by virtue of their power output
or engineering design. These lasers ______ be considered as
hazardous even if all of the accessible laser radiation output is to
_____ to the eye's pupil or ______ into one mm spot on the skin
for ______. These lasers are considered as non-risk lasers, or
exempt lasers. The wavelengths could range from ultraviolet,
visible to infrared region. Class I continuous visible laser should
not have the accessible laser output of _____________. Correct
Answers 1; cannot; direct; focuse; a day; more than 0.39
microwatts
Class 2 laser systems are those emitting visible laser radiation,
in the wavelength range from 400 nm to 700 nm, in pulse or
continuous wave. This is a class of low-power and low-risk
