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

Fusion Circles 1

Fusion Circles is a free activity in Opto, the vision training and vision therapy app for iPad. Practices free space fusion technique.

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Fusion Circles 1

Developed exclusively for Opto. Available now for iPad!


The Fusion Circles technique builds free-space fusion skills by practicing cross-viewing and parallel-viewing of the images. The patient receives feedback on fusion and focus by making the letters appear clearly in 3D


Required hardware: none

Modes: basic, interactive, dynamic

Basic mode: 4 sets of fusion circles are displayed, increasing in difficulty from top to bottom.

Interactive mode: One set of fusion circles are displayed at a time. The user may cycle through the sets of circles using forward and back arrow buttons.

Dynamic mode: The separation of the fusion circles is controlled by a slider. Tap and hold the circles to drag them to any area on the screen.



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 Fusion Circles 1.