Testing method:

1.Sensitive-ColorPhotographic color detection method

The photosensitive color method measures that the entire field of view appears as a reddish purple color, which is classified as photosensitive color.

Place the sample in a green blue or orange yellow color where there is stress. And determine whether the stress property is pressure or tension.

The sample area without stress appears slightly reddish purple.

2. SenarmonMethodCompensation Law

The Senarmont compensation method can be used for quantitative stress analysis and detection. Turn on the power, the entire field of view of the unplanted sample is black brown. Place the sample without rotating the analyzer, and observe the most bright spot, which is the point of maximum stress. Rotate the dial on the analyzer until the brightest spot turns black brown. Record the angle of rotation of the dial and the thickness of the point at this time, and use the formula to convert the stress value.

Calculation formula: stress=optical path difference/(optical path length of the measured point * optical elastic coefficient)

specifications:

• Polarization stress meter light field brightness ≥ 120cd/m2
• Polarization stress meter: The polarization degree at any point of the polarization element is greater than or equal to 99%
• Polarization stress meter construction: A quarter wave plate and a full wave plate (wavelength of 565nm) are placed between the analyzer and polarizer, respectively. The slow axis of the wave plate is at a 90 degree angle to the polarization plane of the polarizer
• There is a measuring device for the rotation angle on the polarizer, with a scale value of 1 degree and a maximum measurement range of 180 degrees

Technical parameters:

• Size: W295 × D375 × H410mm
• Weight: Approximately 10KG
• Effective length and width of the test sample: W200 × D200mm
• Measurement of spatial height: 31-250mm
• Light source: LED light source (with a lifespan of approximately 40000 hours)
• Power supply: AC 220V

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