Photoelastic method is an optical method for measuring stress。It uses transparent material with birefringence properties make structure, with the practical engineering components or parts geometry similar model, similar to the actual components and load applied on the model, can be calculated according to the photoelastic fringe stress model boundary and interior points, then the similarity theory is converted into the stress on the original, its accuracy can meet the requirement of engineering design.Photoelastic method can used to stress component measurement geometry and loading conditions are more complex, especially can measure other method to solve the stress concentration and the internal stress problems。Thus, it’s in favor of  the academic and engineering fields.Especially ，Photoelastic is an important part of mechanics experiment teaching in institutions of higher learning.

        LLH-300 photoelasticimeter was developed by our company; with 300mm aperture, the polarizer and analyzer can manual synchronous rotate. It can be widely used in scientific research and teaching experiment.

The main technical indicators：

1.Aperture：300mm

2.Load：0～300kg

3. light source：LED light source

4. 1/4 wave plate effective diameter：300mm

5.polarizing filter effective diameter：300mm

6. polarizing filter dial：0~360°，minimum scale value 1°

7. 1/4 wave plate dial: 0~360°，minimum scale value 1°

8.Image collection:  import Color video camera

9. mechanical sensor and Digital Indicator

Principle diagram：

                  The principle diagram of the photoelastic apparatus light path

                      Monochromatic light stripe / Mixed light stripe

Experimental schematic And application scope:

        The stress birefringence properties, transparent plastic model can be made in engineering machinery parts, and then simulate the stress components, observation, analysis of color and pattern of polarized light interference, so as to determine the stress distribution within part.

Disk under diametral compression experiment:

U piece of bending combination experiment

  

Pure bending beam experiment：

NOTE: Photoelastic method is intuitive, can directly display the stress concentrated area, and provide the accurate stress concentration values;It not only can get convenient stress but also the internal stress of the  structure . Especially this method is not constrained to the shape or load; it also can analyze the engineering structure stress.