Free Space Random Dot Card Set

The Random Dot Fusion Card Set is a powerful tool designed for eye care professionals to assess and train binocular vision and stereopsis in patients.

This set includes 12 random dot stereograms, with disparity levels ranging from 4 to 26 prism diopters in 2 PD increments, providing a progressive challenge for patients. When properly fused, each image reveals a hidden 3D target. Depending on whether the patient is using crossed (base-out) or uncrossed (base-in) fusion, the hidden images will appear to project outward or recede inward, respectively.

Each card features first-degree fusion targets at the top--a square on the left and an "X" on the right. These assist the patient in achieving proper fusion by aligning the X inside the square through either crossing or uncrossing the eyes. Once alignment is established, the patient lowers their gaze to the random dot field below, where the stereoscopic image should emerge.

If patients struggle to achieve fusion, especially with base-out techniques, clinicians may introduce a fusion aid (such as a pencil or pointer) to stimulate appropriate eye posture. For base-in fusion, instruct patients to imagine converging their eyes at a point behind the card.

The standard working distance is 40 cm, and each card is clearly labeled with its respective disparity value. The answer keys for the hidden images are conveniently located on the back of each card for clinician reference.

This set is ideal for use in vision therapy sessions, binocular vision evaluations, and training programs targeting convergence, divergence, and depth perception.