Radiometers

UDT Instruments, a division of Gamma Scientific, offers an extensive selection of radiometers, radiance meters, irradiance meters and optical sensors to meet your radiometric test and measurement needs.

Combining our wide range of optometers, radiometric sensors and accessories, with our state-of-the-art calibration facilities, allows our applications engineers to assemble and configure custom radiometer systems for nearly any project.

Radiometry is the measurement of radiation in the electromagnetic spectrum. This includes ultraviolet (UV), visible and infrared (IR) light.

Radiometric measurements quantities include: Radiant Flux (Watt); Radiant Intensity (W/sr); Irradiance (W/m2); Radiance (W/m2sr)


 

  • Radiant Flux Measurements (in units of watts) are performed with an instrument known as a flux meter or optical power meter. This type of testing is typically used for characterizing the total output of sources such as:Lasers, LEDs, Lamps and Fiber-Optic Systems
  • Irradiance Measurements (in units of W/m2) are performed with an irradiance meter. This involves the measurement of the radiant flux incident upon a surface, per unit area. Such measurements are important in the following fields: Medical, Biological and Remote Sensing
  • Radiant Intensity Measurements (in units of W/sr) are performed with an instrument that may be described as an optical intensity meter. This type of testing is typically used for characterizing the output of a relatively small source in a particular direction. Typical devices under test include: LEDs, UV Lamps and IR Lamps
  • Radiance Measurements (in units of W/m2sr) are performed with a radiance meter. This involves measuring the light emitted in a particular direction by a given spot on the surface of an extended source. Such measurements are important in fields such as: Remote Sensing, Avionics and Night Vision

Specifying a Radiometer System

Selecting a properly calibrated radiometric head and the right readout device are important in obtaining accurate results.

The sensor head converts electromagnetic radiation into an electrical signal. The readout device then receives this signal and interprets it. A properly calibrated measurement system will measure the light source and display the measurement in the appropriate optical units.

The readout unit should be selected according to its features, and the detector head should be selected according to its power measurement range, wavelength calibration and size. The two matched together will accurately measure the source in the correct optical units.

Radiometer and Radiometry Resources from Gamma Scientific

Gamma Scientific Radiometers

flexOptometer Benchtop Radiometer

High-performance radiometer designed to operate as a stand-alone instrument or computer-controlled radiometric measurement system. Available with a single head, or up to four interchangeable detector heads. Electronic design is based on Gamma Scientific’s TIA-3000 measurement system, which serves as the primary working standards of several National Standards Labs. Laboratory grade accuracy and durability ensures that the flexOptometer will operate in the most rigorous production line environments.

NVIS Radiometer: NVG-4040

The NVG-4040 has a unique ability to perform NVIS-A, NVIS-B and NVIS-C radiance measurements. Lightweight, portable and cost-effective, it conforms to MIL-L-85762A and MIL-STD-3009. The NVG-4040 is optimized for a full range of photopic applications, and is ideally suited for measuring displays and instrument panels used with night-vision goggles.

Model 471 Portable Radiometer

The model 471 handheld radiometer is designed to be used for radiometric measurement in the laboratory or field testing environment. It features high-accuracy measurements, wide dynamic range, high-speed update rate and a large calibration capacity. All calibrations are traceable to the National Institute of Standards Technology (NIST).

TIA-3000 Measurement System

Detector-based absolute standards for capturing a wide range of measurements. Configurations include thermo-electrically cooled silicon and indium gallium arsenide (InGaAs) detectors with options for radiometric correction filters, flat-response filters, trap detectors and ANVIS-compatibility filters. Standard calibrations, directly traceable to NIST, are available for any configuration of the TIA-3000 from Gamma Scientific’s world-renowned standards lab.

Radiometric Sensors from UDT Instruments

UDT Instruments produces precision radiometric sensors for diverse applications and are ideally suited for OEMs and value-added resellers. UDTi radiometric sensors provide industry leading accuracy, and each sensor from UDT Instruments includes a NIST-traceable calibration from our NVLAP accredited laboratory.

uRAD-LL Handheld Radiance Meter

This radiance meter bundle combines a filtered silicon sensor with a fixed-focus lens to provide non-contact radiance measurement of an area on the surface of an extended source. Spot size is dependent working distance, which ranges from 17 mm to infinity.

uRAD-E Irradiance Meter

This irradiance meter bundle combines a broadband silicon sensor with a benchtop optometer to provide simple and accurate measurement of irradiance. The system’s calibration is programmed into the benchtop optometer. Measurement results are displayed by the optometer in units of Watts per square meter (W/m2), and digital data can be acquired directly via PC.

Optical Accessories

Photosensors can be equipped with various types of optical accessories to form sensor head assemblies suitable for diverse types of measurements. UDT Instruments offers a range of preconfigured sensor heads, as well as the following optical components to enable configuration of custom sensor heads for the measurement of flux, illuminance, irradiance, intensity, luminance, or radiance.

Flexoptometer (Radiometer/Photometer) Specifications

 

Electronic Integrator
Eight Photometric/Radiometric Ranges Four Integrate Ranges
Range-to-Range Linearity < 0.1% for most ranges (< 0.25% for most sensitive range) Range-to-Range Linearity < 0.1% for most ranges (< 0.25% for most sensitive range)
Sensitivity: 10-15; to 10-3 Amps Sensitivity: 10-14 to 10-3 coulomb
Resolution: 1×10-15 Amps Decay Error: analog-approx. 0.01% / sec
Dark Current Suppression: 50 nA Max Digital-holds reading indefinitely
Noise: < 3×10-15 Amps
Frequency Roll-off: < 10 Hz on most sensitive range
Photometric/Radiometric Ranges
Photometric Units Sensor and Range
Luminous Intensity Model 424: 0.00001 mcandelas to 10000 candelas
Illuminance Models 211 and 268P: 0.00001 milliLux to 10000 Lux
Luminance Model 2153: 0.0001 millicandela/m² to 100000 candela/m²
Illuminant Energy Models 211 and 268P: 0.00001 milliLux*seconds to 10 Lux*seconds
Radiometric Units Sensor and Range
Irradiance Models 221 and 247: 0.000001 nanoWatts/cm² to 1000 microWatts/cm²
Radiant Energy Models 221 and 247: 0.00001 nanoJoules/cm² to 1 microJoules/cm²
Radiance Model 247 with 1153: 0.00001 nanoWatts/cm²/steradian to 10 milliWatts/cm²/steradian
Sensors and Accessories
UV/Visible Photometric
211: Silicon Sensor (350-1100nm) 1cm² active area 211: Photometric Sensor with Cosine Receptor (Illuminance)
222: Silicon Sensor (200-400nm) 1 cm² active area 263: Miniature Photometric Sensor (Illuminance)
228: Silicon Sensor for HeNe Laser (633nm) BHR Compliance 268P: Low-Profile Photometric Sensor with Cosine Receptor
260: Miniature Silicon Sensor (350-1100nm) 0.34 cm² active area 2153: Photometric Sensor with 13 degree FOV Lens (Luminance)
268BLUE: Low Profile Blue Optimized 450 nm Sensor 265: Photometric Display Brightness Sensor (Luminance)
268UVA: Low Profile UVA Optimized Sensor Head (365 nm) 268M: Mini Photometric Display Brightness Sensor (Luminance)
268UVC: Low Profile UVC Optimized Sensor Head (254 nm) 424: LED Photometric Sensor (CIE 127 Luminous Intensity)
Radiometric Laser Power
247: Flat Response Sensor 264: Miniature Attenuated Laser Sensor Head
262: Miniature Flat Response Sensor 268LP: Low Profile Laser Sensor Head
264: Attenuated Laser Sensor Head Infared
268R: Low Profile Flat Response Sensor 261: Miniature Infrared Germanium Sensor (800-1750nm)
424R: LED Radiometric Sensor (CIE 127 Luminous Intensity) 280: Miniature Infrared InGaAs Sensor (800-1750nm)
General Specifications
Automatic/Manual ranging
Microprocessor Controlled Functions
High Voltage circuit for photomultipliers (300-1500 Volts)
Thermo-electric coolers for Sensor and filter stabilization
USB, RS-232, RS-485 and IEEE-488.2 Communications
Analog Output
Power Input: 12.0 volts DC
Operating Temperature Range: 0 to 50° C
Humidity: 0% to 95% RH non-condensing