3. Subjective refraction
Refraction with i.Polatest®
After the objective technical measuring process with the i.Profiler®, we then conduct an examination to determine your prescription on the basis of your own subjective information.
Analysing the various aspects of your vision.
Unlike many other examination methods, we determine your visual performance for both of your eyes at the same time. To take into account the complexity and multidimensionality of vision, we use special tests in the new ZEISS i.Polatest® to analyse further aspects of your vision – your 3D vision and the interaction of your two eyes, for example.
With the aid of the measuring and correction methodology devised by Haase (MKH), it is possible to determine deficiencies in the interaction of the eyes. Latent squints, also known as associated phoria, leading to visual problems (e.g. double images or eye fatigue) can be corrected by prismatic lenses.
Prisms can be integrated into spectacle lenses to enable natural, comfortable and relaxed interaction of the two eyes.
Some wearers require different powers for their left and right eyes. One eye can be short-sighted, and the other long-sighted, for example. In combination with other factors, this difference in powers, also known asanisometropia, may mean that the visual centre of the brain receives two differently sized images. Such aniseikonia may result in an impairment of spatial vision. With the aid of individually produced lenses, the image sizes are matched so that the brain can process them without difficulty again.
It is important to understand binocular vision because the information provided by the two eyes is processed in the brain into one three-dimensional image. Only the perfect interaction of the eyes allows a perfect 3D image and natural spatial perception, permitting the correct assessment of the size and distance of objects.
We also use the Polatest® N Classic near vision testing system which consistently supplements our distance vision testing technology. Here we use binocular texts in order to check your binocular reading ability. Binocular reading ability is important for determining the final near prescription – after all, it is these values that determine what lenses are best suited for your needs.