Technical Reference

Industrial Lighting & Optics Glossary

Definitions for terminology used throughout industrial lighting, LED systems, optics, electronics, thermal design, manufacturing, and machine vision.

Industrial lighting combines terminology from illumination engineering, optics, electronics, mechanical design, manufacturing, thermal management, environmental protection, and machine vision. The definitions below provide practical context for terms used throughout Starlight 2007.

Lighting Terms

Light Output & Distribution

Beam Angle

The angular spread used to describe a light beam. The complete distribution may extend beyond the nominal beam angle.

Illuminance

The amount of luminous flux reaching a surface. Illuminance is commonly expressed in lux.

Lumen

A unit used to describe luminous flux, representing visible light output weighted according to human visual response.

Lux

A unit of illuminance representing one lumen distributed over one square meter.

Uniformity

The consistency of illumination across a target area rather than the light level at only one point.

Glare

Visual discomfort or reduced visibility caused by excessive brightness or strong reflections within the field of view.

Color

White-Light Characteristics

CCT

Correlated color temperature describes the general appearance of white light, often characterized as warmer or cooler.

CRI

Color Rendering Index is one metric used to describe aspects of how colors appear under a light source compared with a reference.

Spectrum

The distribution of optical energy across wavelength. Two visually similar white sources can have different spectra.

Wavelength

A property associated with electromagnetic radiation that relates to spectral position or perceived color within visible light.

Optical Terms

Controlling & Directing Light

Lens

An optical component that changes the direction or distribution of light through refraction or related optical behavior.

Reflector

A component that redirects light by reflection and can contribute to beam shape and distribution.

Diffuser

An optical element used to scatter or redistribute light, often reducing visible source points or smoothing a distribution.

Optical Filter

A component designed to selectively transmit, attenuate, or reject portions of the optical spectrum.

Optical Window

A transparent protective element placed in an optical path to isolate internal components from the environment.

Light Guide

An optical structure that transports light from a source toward another location or emitting surface.

Collimation

The process of reducing the angular spread of light so rays travel more nearly parallel.

Refraction

The change in direction that can occur when light passes between materials with different optical properties.

LED Terms

Light Sources

LED

Light-emitting diode. A semiconductor device that produces light when operated electrically.

LED Module

An assembly containing one or more LEDs along with a substrate and sometimes additional electrical, optical, or mechanical components.

COB LED

Chip-on-board LED technology in which multiple semiconductor emitters are integrated closely on a common substrate.

LED Array

A group of LEDs arranged electrically and mechanically to create a larger or differently shaped light source.

LED Driver

Electronic circuitry used to establish or regulate the electrical operating conditions required by LEDs.

LED Heat Sink

A thermal structure used to spread and transfer heat away from LED assemblies and into the surrounding environment.

Electronics

Power & Control

PCB

Printed circuit board. A substrate that mechanically supports and electrically connects electronic components.

Power Supply

Electrical equipment that converts or conditions input power for downstream electronics or lighting loads.

Dimming

Control of lighting output by altering the operating conditions or command signal supplied to the lighting system.

Connector

A removable electrical interface used to join conductors, cables, equipment, boards, or assemblies.

Sensor

A device that detects a physical condition and produces information that can be used by a control system.

Control Module

An electronic assembly that manages switching, dimming, communication, logic, sensing, or related functions.

Engineering

Thermal & Environmental Terms

Thermal Management

The design of heat-transfer paths used to control operating temperatures within LEDs, electronics, housings, and assemblies.

Thermal Interface

The physical region between two components through which heat must pass, such as between an LED board and metal housing.

Ambient Temperature

The temperature of the surrounding environment in which equipment operates.

IP Rating

A classification system used to describe defined levels of protection against solid-object and water ingress.

Ingress

The entry of dust, water, or other environmental material into an enclosure or assembly.

Gasket

A compressible sealing component positioned between mating surfaces to help restrict environmental entry.

Machine Vision

Inspection Terminology

Machine Vision

The use of imaging hardware, illumination, optics, processing, and software to inspect, measure, identify, or guide industrial processes.

Ring Light

A lighting geometry that places multiple light sources in a ring around a camera or optical axis.

Backlight

Lighting placed behind a target relative to the camera to produce silhouette or transmitted-light contrast.

Low-Angle Lighting

Illumination directed across a surface at a shallow angle to emphasize edges, raised features, scratches, or surface texture.

Polarization

Control of the orientation of light's electromagnetic field, sometimes used to manage reflections in imaging systems.

Strobe Lighting

Short-duration illumination synchronized with image capture or machine operation.

Manufacturing

Production Terminology

CNC Machining

Computer-controlled material-removal processes used to produce precision component geometry.

Aluminum Extrusion

A manufacturing process used to create continuous aluminum profiles with a repeated cross section.

Die Casting

A metal-casting process that forms repeat component geometry using dedicated tooling.

Injection Molding

A manufacturing process in which polymer material is formed inside a mold to create repeat component geometry.

Sheet-Metal Fabrication

Cutting, forming, joining, and finishing sheet material to produce panels, enclosures, brackets, and related structures.

Anodizing

An electrochemical surface-treatment process used with aluminum for selected protective, wear, or appearance requirements.

Prototype

A development version of a component or assembly used to evaluate design, function, manufacturing, or integration.

Production Assembly

A repeat-manufactured product or subsystem built using controlled components, processes, and assembly methods.