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another can be identified at the zonę of maximal plastic deformations. It is exactly in this zonę where the implant destruction takes place. On the other hand, figurę 6 shows the shadow image of the implant whose upper part of the tip is displaced by 5.1 mm. This image allows us to assess the implanf s bending angle only.

Fig. 4. Scheme of optical system for forming of speckle pattern of implant with CCD camera: 1 - He-Ne laser, 2 - implant, 3 - aperture (stop), 4 - lens, 5 - CCD camera.

a)    b)    c)

Figurę 5. Formation of displacement field Figurę 6. Shadow image of the

of a bent implant with the aid of ODSC implant bent by 5.1 mm.

method: a) implant imagea; b) implant

speckle-image, bent by 5.1 mm; c)

displacement field of the implant’s

surface by one pointed sideways loading

onto the top of its tip.

4. Conclusions

This study established a rangę of optimal parameters for optical schemes for systems of shadow image and speckle image formations. The experiments were conducted with implants which underwent pointed bending loadings by means of the shadow and ODSC methods. The study demonstrated that the ODSC method is morę effective than the shadow one, sińce it allows to determine the distribution of displacement fields and surface deformations and, on this basis, to assess the zones of maximal plastic deformations and most likely places of implant destruction.

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