Stress on the spine (investigation by the “Polariscope using the photoelastic method”)


Hello everyone. The number of people who work at home is increasing due to the influence of the recent coronavirus.

I guess that more and more people are working with sitting for a long time. I want to take the right posture because my posture may damage my physical condition. In this issue, we will introduce examples((1) and (2)) in which the effects of posture on the body have been investigated by the “Polariscope using the photoelastic method”.


■ Stress on the spine

The photoelastic model for evaluation is made of transparent resin based on the X-ray photograph, and photos of photoelastic fringes is posted below when the load of each posture is 5 kgf.

The number of fringes increases in the order of a, b, c, d, indicating an increase in bending stress.

This “strain inspection by the photoelastic method” is used in various fields because it is possible to know the magnitude of stress from the number of fringes obtained by using polarized light and the stress concentration part from the dense position.


                                           Radio Photograph




Luceo develops, manufactures and sells polariscopes that apply the photoelastic method. You can check its operation at the showroom of Luceo headquarter. We also accept sample measurements, so please feel free to contact us.


Polariscopes LSM Series General Catalog

Contact us

Luceo Co., Ltd. / Sales Dept.

30-9 Ohyama-kanaicho, Itabasi-ku, Tokyo



■ References

(1) Yoshiharu Masuda: Photoelastic study of the human lumbar spine in the sagittal plane, Proc. Of the 17th conference of the Photoelastic Society of Japan No.17, pp.71-74, 1995

(2) Ryoichi Yamazaki, Motohiro Miura: Structural analysis of photoelastic experiments, Nikkan Kogyo Shimbun, pp.190-192