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P.O. Box 716
Sunapee, NH 03782-0716
603-526-2420 (office), 603-526-2729 (fax)

Goniometric (spectral)

Goniometric (photometric)


Gloss and Reflectance

Haze and Clarity

Online Systems
  Glossmeter GR-2
  Glossmeter GR-4
  Color CMTS-5000
  Color CMTS-5000T
  Hazemeter HMS-3
  Transmittance TM-100M


The Murakami Team
Murakami Products
Avian Technologies LLC
Murakami Corporate




Please refer to the gonio measurement overview page for general considerations of the various instrumentation.

Of the three goniophotometric instruments, the GP-5 is the lowest cost alternative. To enable this competitive price point, the GP-5 ulitilizes a manual incident angle adjustment, manual flop angle adjustment, and the use of a silicon photodiode detector. This instrument is therefore suited for those applications where only a few incident angles are required, and the samples are large and reflective enough for the silicon photodide detector. Customers with sample requirements that are very small or very dark should consider the GP-200 or the GP-700, both of which are equipped with a photomultiplier tube detector.

The GP-5 is suitable for a wide variety of applications including:

  • Analysis of the properties of the transmitted light for plastics or glass
  • Measurement of the roughness of metals or paints
  • Analysis of the optical properties of materials with magnetic paints
  • Analysis of the properties of paper
  • Analysis of the optical properties of hair
  • Investigation of the optical appearance of wood
  • Evaluation of surface properties of high gloss materials
  • Investigation of the optical appearance of textile or fabrics
  • Measurement of the properties of transmittance for diffuser, prism sheet and polarized film of LCD back light.

Operational Information

The beams from the light source converge onto the pin hole field stop through the condenser lens, and are then converted into parallel beams through the collimator lens. These beams reach the specimen plane through the beam iris. The beams are reflected from (or transmitted through) the specimen plane and then focused onto the detector via a final field stop, focusing lens, and receiving iris. Thus, the reflectance, transmittance and diffuse reflectance of the specimen can be obtained by measuring the light intensity relative to the reference standard.


Light source

Halogen 12V/50W


Silicon Photodiode

Source iris

5 mm diameter

Receptor aperture angle


Receptor angular resolution


Incident angle


Specimen table inclination angle

0 to 15°manually-adjusted

Receptor rotation angle

180°±0.3° automatically-adjusted

Photometric accuracy

 Within ±2% full scale


Within ±2%

Sample size range

min 50 x 50 mm
max 90×110 mm

max thickness 8 mm

Power consumption

300W approx., 100V AC


Overall L 465× W 760×H 340 mm


approx. 50 kg

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