Light Measurement

PR-715

PR715 - Spectroradiometer

Overview

The PR-715 is a sophisticated, lab grade, fast scanning spectroradiometer with a near infra red measurement capability. It is a stand-alone instrument that maintains the exceptional performance that has made the SpectraScan series the industry standard for accurate spectroradiometry in the industries such as Automotive, Aerospace, Computer, Lighting and Display Manufacturing.

The PR-715 is designed to quickly measure (in as little as 50 milliseconds) the intensity and colour of light sources, displays and reflective or transmissive samples with NIST-traceable accuracy. It is the perfect instrument for manufacturers to establish measurement correlation with their vendors and customers to ensure that products meet the tight photometry and colourimetry specifications. One of the key features that makes the PR-715 an essential tool for both R&D and QA/QC testing is it's ability to precisely measure areas as small as 0.02 mm with the highest accuracy and repeatability.

Features

Stand-Alone Optical Head

Spectral measurements are made in near real-time as light passes through a measuring aperture, is dispersed by a diffraction grating and then imaged onto a multi-element detector. The Automatic Adaptive Sensitivity feature optimizes the dynamic range and increases Signal-To-Noise by selecting exposure times based on the available signal level. World famous Pritchard™ optics permit precise viewing of the target while allowing only the measured optical radiation to pass through to the detector.

The incoming light is dispersed by a holographic diffraction grating and the dispersed spectrum is measured by a thermo-electrically cooled silicon diode array detector. The PR-715 measures Spectral Power Distributions in the visible/NIR range from 380-1068 nm. A visible only range version is also available, see the PR-705. Optics are designed to minimize polarization error resulting in accurate measurements of polarized sources such as LCDs. Since the cooled detector is housed in a hermetically sealed, pressurized chamber, the PR-715 makes extremely stable and repeatable measurements.

State-of-the-Art Optical Design

One of the primary beneifits of this versatile instrument is its portability as it can be used stand-alone. This allows users to make outdoor measurements and test instrument panels inside cockpits and automobiles. Two powerful on-board microprocessors control the hardware and mathematically calculate photometric and colourimetric values for the acquired spectral data during a measurement. As a result, there are no errors in colour accuracy due to filter mismatches from the CIE specified functions as in the case of filter colourimeters. The PR-715 provides accurate answers for the luminance and colour regardless of the source distribution.

Greater Flexibility and Enhanced Sensitivity

The PR-715 can accommodate from one to six measuring fields (2°, 1° , 1/2° , 1/4° , 1/8°  and special slits). If multiple apertures are selected at the time of purchase the result is a flexible system that can measure a wide range of spot sizes without changing the working flexible distance to focus the MS-55 lens. Variable apertures and a wide selection of objective lenses make it possible to measure virtually any target size down to 0.02 mm. Because the measuring aperture is the entrance slit to the spectrometer, the instrument bandwidth depends on the aperture used. In order to measure narrow band sources such as laser diodes, small apertures (1/4° or 1/8°) should be chosen to obtain an optical bandwidth of 5 nm.

The PR-715 can measure incandescent sources at light levels as low as 0.0015 cd/m². It can even measure the black levels required to characterize the contrast ratio of various displays.

Remote Operation and Data Transfer

Remote operation from user-defined software running on a host computer is possible by sending ASCII commands over an RS-232 port to control the PR-715 (built in Remote Mode software). A built-in centronics parallel port is available for connecting to standard PC printers and a SYNC IN/SYNC OUT connector is provided for pulsed light measurements.

The PR-715 can be operated from a PC using SpectraWin™ software. SpectraWin™ is Windows-based software that gives you the power to make measurements, view data in customized graphics displays, perform calculations on stored data and create macros for automation.

Measurement Capabilities

  • Luminance (Illuminance, Luminous flux, Luminous intensity require appropriate optional input optics)
  • Radiance (Irradiance, Radiant flux, Radiant intensity are optional)
  • 1931 CIE x,y - 1976 CIE u', v' chromaticity coordinates
  • Tristimulus Values X, Y and Z
  • Correlated Colour Temperature (CCT) in Kelvin
  • CIE 2° or 10° Observer calculations

Additional Measurement Capabilities using SpectraWin™ software

  • Dominant Wavelength, Excitation Purity
  • Percent Transmittance/Reflectance
  • Colour Rendering Index (CRI)
  • L*c*h* and Δ L*c*h*
  • Go/ No Go chromaticity testing
  • Spectral Power Distribution (SPD) data and Spectral Radiance
  • ΔLuminance, Δxy, u', v' and ΔCCT
  • L*u*v*, L*a*b* and ΔE colour difference

Manufactured by Photo Research

Specifications

Wavelength Range

380 - 1068 nm

Spectral Accuracy

± 4 nm

Spectral Bandwidth

≥ 5 nm. Bandwidth is dependent on aperture size

Available Apertures

2°, 1°, 1/2°, 1/4°, 1/8°. Select at time of purchase. Special horizontal aperture slits available

Minimum Measuring Area

0.12 mm with standard MS-55 lens and 1/8° aperture
0.02 mm with optional MS- 5X lens and 1/8° aperture

Luminance Sensitivity for Illuminant A

0.0015 cd/m² for 2° aperture and MS-55 lens

Luminance Accuracy

± 2% to NIST traceable luminance standard at 2856 K

Luminance Repeatability

The standard deviation of repeat measurements over a 30 minute period is less than 0.1%

Colour Accuracy for Illuminant A

x ± .003 y ± .002

Colour Repeatability

± .0005 at a CCT of 2856 K

Polarization Error

Less than 5% when measuring linearly polarized sources in the visible range

Visual Field of View

8.5° with the MS-55 lens

Interfaces

RS-232 (serial), IEEE-488 (parallel - optional), Printer (parallel)

Digital Resolution

16 bits

Power

100V - 240V AC / 50-60 Hz

Weight

5.62 kg

Operating Temperature

1°- 30° C

Humidity

0 - 90% non-condensing

PR-715 Field Coverage Chart (Bandwidth in nm)

Accessory

Working Distance

2° (40)

1° (20)

0.5° (10)

0.25° (5)

0.125° (5)

MS-55
Variable Focus

44mm
305m

1.93 mm
10.66 m

0.97 mm
5.33 m

0.48 mm
2.67 m

0.24 mm
1.33 m

0.12 mm
0.66 m

MS-1X
Fixed Focus

96 mm

1.93 mm

0.97 mm

0.48 mm

0.24 mm

0.12 mm

MS-2.5X
Fixed Focus

45 mm

0.76 mm

0.38 mm

0.19 mm

0.10 mm

0.05 mm

MS-5X
Fixed Focus

28 mm

0.38 mm

0.19 mm

0.10 mm

0.05 mm

0.02 mm

MS-77
Fixed Focus

108 mm

0.64 mm

0.32 mm

0.16 mm

0.08 mm

0.04 mm

PR-715 Sensitivity Chart

Accessory

Working Distance

Units

2°

1°

0.5°

0.25°

0.125°

MS-55

44mm –
Infinity

cd/m²

0.0015-850

0.005-3400

0.02-13700

0.08-054800

0.33-219000

MS-1X

96 mm

cd/m²

0.0015-850

0.005-3400

0.02-13700

0.08-054800

0.33-219000

MS-2.5X

45 mm

cd/m²

0.0015-850

0.005-3400

0.02-13700

0.08-054800

0.33-219000

MS-5X

28 mm

cd/m²

0.0023-1250

0.008-5100

0.03-20500

0.12-82000

0.48-328000

MS-77

108 mm

cd/m²

0.0023-1250

0.008-5100

0.03-20500

0.12-82000

0.48-328000

CR-55

N/A

Lux

0.022-10750

0.07-43000

0.26-172000

1.03-687500

1.54-2750000

FP-55

N/A

cd/m²

0.0023-1250

0.008-5100

0.03-20500

0.12-82000

0.48-328000

LR-55

N/A

mcd

0.001-550

0.004-2300

0.016-9000

0.64-46000

0.256-144000

The sensitivity values are for a 2856K incandescent source at a precision of 10% relative standard deviation

Schematics

PR-715 Schematic