Schaeffel Lab

Neurobiology of the Eye

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The laboratory has accumulated expertise in photorefraction in all kinds of animals, and also in humans. The expertise in automated photorefraction merged into a commercially available photorefractor, the "PowerRefractor", which is optimized mostly for use in humans but can also be adapted to measure animals.

In 2001, the PowerRefractor and its patent were handed over to the company "PlusOptiX" in Nuernberg, Germany, which started its professional development and marketing.

In 2003, the company anounced insolvency. It was refounded under the same name and is currently developing other versions of the original refractor. Frank Schaeffel is not involved in these developments and is NOT responsible for their performance.

Finally, photorefractors for fast scanning of the peripheral refractive state are under development.

Video Gaze Tracker

There was also technology development toward an automated and self-calibrating video gaze tracker (see Frank Schaeffel). This device has not been converted into a commercially available product, but various later generation video gaze trackers and head trackers were developed with firewire or USB2 cameras, and are in use in industrial cooperations.

measure lens tilt

In addition, a device was developed to measure lens tilt and decentration in normal and pseudophakic subjects (in press at IOVS 2008).

Automated optomotor measurements

Since the mouse is an important animal model for various human diseases, including vision disorders, automated and labtop-based devices were constructed and programmed for behavioural measurements of visual performance, and for pupillography in alert mice, only restrained by holding their tails.