Lensmeter
![](https://upload.wikimedia.org/wikipedia/commons/thumb/2/20/Lensmeter-2.png/220px-Lensmeter-2.png)
Scheme of a simple lensmeter:
1 - eyepiece
2 - thread net
3 - objective
4 - Kepler telescope
5 - lens stop
6 - lens to be measured
7 - collimator
8 - thread net
9 - light source
10 - collimator
11 - adjustment mechanism
12 - power drum (± 20 Diopters )
1 - eyepiece
2 - thread net
3 - objective
4 - Kepler telescope
5 - lens stop
6 - lens to be measured
7 - collimator
8 - thread net
9 - light source
10 - collimator
11 - adjustment mechanism
12 - power drum (± 20 Diopters )
The vertex power meter ( synonym : lens meter) is a measuring device that is used in ophthalmology and optics to determine the vertex power . This then determines the refractive index of optical vision aids ( glasses ). A positive vertex power is always used when parallel rays of light that fall on the lens of the visual aid are refracted towards one another. The measuring device ultimately measures the "strength" of the visual aid and gives the spherical and cylindrical values in diopterson. The device is manufactured under DIN EN ISO 9337.
Since the optic lens on the eye side is decisive for spectacle lenses, the surface on the eye side must be measured on the lensmeter.
Web links
Individual evidence
- ↑ servant optics lexicon
- ^ Peter A. Schmitt: Langenscheidt technical dictionary technology and applied sciences . Langenscheidt Fachverlag, 2004. ISBN 978-3861172338