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Gerull Labs LLC (G-Labs) Modern Vision Therapy resources for Apple iPad.

Strings and Spheres

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Strings and Spheres

Developed exclusively for Opto. Available now for iPad!


Strings and Spheres builds free-space fusion skills by practicing cross-viewing of the targets. The patient receives feedback on fusion and focus by fusing each sphere on the string progressively, making the image appear 3D.

This exercise features the strings and spheres in different orientations to practice fusing at in a variety of ways. See screenshots below.

How to Purchase: Available as an in-app purchase in Opto, the vision training app for iPad. May be purchased individually ($3.99 USD) or for a discounted price as part of Expansion Bundle 1. Download Opto and browse the in-app library to purchase.

Required hardware: none

Modes: none


Like all activities in Opto, a report is generated including the date and duration of the exercise. A patient assessment is also recorded if the user is signed into his/her personal profile. 


Sample screenshots:


Download Opto for iPad to access the Strings and Spheres.