Illuminate vision charts homogeneously.


With LUVIS and LUVIS mini it is finally possible to illuminate contrast and vision charts correctly and homogeneously. As a result the measurement of contrast sensitivity is getting easier because you do not have to worry about how to illuminate the charts correctly.

But it will also become more precise: With the LUVIS products the vision charts are illuminated homogeneously. This means that the lightness or rather luminance do not have big offsets. For instance with LUVIS mini you will achieve a maximal deviation of +/- 3% all over the chart. Previous processes and requirements (ISO) are about +/- 25 %. Especially in contrast tests these can lead to crucial differences of the result.

Occupational doctors (German FeV of 2011)

Since 2011 every occupational doctor or physician has to check the contrast vision at the survey of the driving licence for professional purpose. With LUVIS the affordable MARS and Pelli-Robson charts can be illuminated homogeneously.

The DOG recommends on the one hand insight devices which are investments above 3.000 € and rarely portable. On the other hand they are arguing in support of the  MARS and Pelli-Robson charts with which you check the photopic contrast sensitivity.

The difficulty to illuminate the charts in different places is solved with the LUVIS products. External light sources are not necessary. Consequently you can thoroughly trust the results as part of the driving licence test and all test persons receive fair test requirements.

Clinics / scientists / ophthalmologists (for studies)

In clinical studies the result of a vision test is decisive for the success of the study. Standardized illumination is not only important for the visual acuity test but all the more important for the contrast sensitivity test. Already with little deviations of illumination your test person would not recognize a lower contrast step.

Particularly in multicentric studies it has to be paied attention to the fact that all centers should use the same illumination. If it is not the case the question arise how comparable and reliable the measurements are. Therefore it is not enough if the centers will use the same vision contrast chart but however illuminate them in different ways: If center A use a table lamp, center B the fluorescent light of the room lightning and center C a LED-lamp there will be highly probable emerged three different illuminations. Therby the measurements of the centers are neither comparable nor wll illuminated.

Especially the MARS and Pelli Robson charts are not easy to illuminate homogeneously. In most cases the middle of the chart is a little bit lighter than the edges or there are reflections on the optotype with the result that it is emphasized through reflections in the print ink. More informations you will find in the scientific articles of the eye clinic Tuebingen: Durst et al. (Br J Ophthalmol 2011; 95:1506-1508) and Raabe, T. et al. (Klinische Monatsblätter Augenheilkunde 2014; 231: 798-809).

With LUVIS products you will gain immediately and without required install measures reproducible results and create standardized conditions for all test persons.

Optometrists / opticians (screening)

Do you check the contrast sensitivity during a refraction or follow-up check? Or maybe during a preinvestigation? If the answer is yes you should definitely check if the illumination is correct and homogeneous. Furthermore it should be considered if it is summer or winter or if the sunlight is directly shining into the screening room. Whereas with LUVIS you can just lean back and relax!

According to the statistics 70 % of the refractions in Germany take place at the optician or optometrist. Especially the contrast sensitivity of the older people decrease obviously often because of a cataract (lens opacification). You can and should reveal these cases. Because the older people are indeed often perfectly corrected but suffer from low contrast sensitivity. As a consequence they endanger themselves and other traffic participants.

Introduce the contrast sensitivity test from a particular age to your standard investigation! For instance you can already establish with only LUVIS and a MARS chart screening of the vision contrast with low efforts. Therewith you will create reliable investigations and become a contact-point for a grateful audience.