APPENDIX G. GLOSSARY-continued

TB 430133

Radiant Exposure

The energy per unit area incident upon a given surface in a given time

interval. It is used to express exposure dose to pulsed laser radiation and is

commonly expressed in J/cm2.

Radiant Power

The time rate of flow of radiant energy (expressed in Watts). Commonly

used to describe the output of CW lasers or the average radiant output

power of repetitively pulsed lasers.

Radiofrequency

Electromagnetic energies between 3 kHz and 300 GHz.

Radome

An RF transparent cover that is used to protect an antenna from the

environment.

Repetitively Pulsed Laser

A pulsed laser with reoccurring pulsed output. The frequency of the pulses

is termed pulse repetition frequency (PRF).

Retina

A structure of the eye composed of layers of neural tissue, including

photoreceptors, responsible for absorbing incoming photons and converting

their energy to an electrical impulse.

Scotoma

Loss of vision in part of the visual field; blind spot.

Slot Antenna

An antenna with a long narrow aperture that is normally one half wavelength

long.

Specific Absorption Rate (SAR)

Used as the fundamental parameter in biological effects studies and in the

human exposure criteria. The units are watts per kilogram.

Specular Reflection

A mirrorlike reflection.

Transceiver

A communications device capable of both transmitting and receiving

radiofrequency radiation.

Transmitter

A circuit used to produce and/or tansmit a radiofrequency signal into space.

UHF

Ultrahigh Frequency; the band of frequencies between 300 and 3000 MHz.

Uncontrolled Area

An area where individuals who have no knowledge or expectations that they

may be RF exposed.

Ultraviolet Radiation

Electromagnetic radiation with wavelengths between soft xrays and visible

light. This region is broken down into 3 spectral bands by wavelength: UVA

(315400 nm); UVB (280315 nm); UVC (200280 nm).

VHF

Very high frequency; the band of frequencies between 30 and 300 MHz.

Visible Radiation

Electromagnetic radiation that can be detected by the human eye. It is

commonly used to describe wavelengths that lie between 400 and 700 nm.

Watt

The unit of power or radiant flux; 1 joulepersecond. Used principally with

continuous wave (CW) lasers.

Watt/cm2

A unit of measure expressing energy applied per unit time over some area.

Waveguide

A transmission line capable of confining and guiding electromagnetic energy

from a generator or amplifier to some other location.

Wavelength

The distance between two points in a periodic wave that have the same

phase.

Whole Body (WB) Exposure

Refers to a uniform RF field over the entire body.

G-3/(G-4 blank)