StereoAcuity

Evidence-Based Digital Stereopsis Screening

Screening Tool
This is a screening tool, not a diagnostic device. Results do not constitute a medical diagnosis. Consult a qualified eye care professional for comprehensive stereoacuity assessment.

Requirements

Red-Cyan anaglyph glasses

Credit/debit card for screen calibration

Standard viewing distance (~50 cm)

Well-lit room, comfortable brightness

Methodology

4-Alternative Forced Choice (4AFC) using dynamic random dot stereograms with anaglyph encoding. Descending method of limits with 11 disparity levels (800″–20″). Three presentations per level; ≥2/3 correct required to pass (Randot criterion).

Scientific Articles:

Bonfanti S, et al. "Evaluation of stereoacuity with a digital mobile application." Graefes Arch Clin Exp Ophthalmol. 2021;259(9):2843-2848. PMC8380567

Tittes J, et al. "Assessment of stereovision with digital testing in adults and children with normal and impaired binocularity." Vision Res. 2019;164:69-82. DOI: 10.1016

Barnett-Itzhaki G, et al. "Evaluating distance stereoacuity in children 4-17 years of age with a novel digital application." J AAPOS. 2024;28(3):103904. DOI: 10.1016

Estimated time: 3–5 minutes

Screen Calibration

We need to measure your screen's pixel size for accurate disparity calculation.

Hold a standard credit card (85.6 × 54 mm) against your screen.
Drag the rectangle to match your card's size.

↔ Drag edges to resize

— px/mm — mm/px

Set your viewing distance (eyes → screen). You can use your camera for live measurement or set it manually.

Privacy & Consent: We use MediaPipe Face Detection to estimate distance based on facial bounding box width. No images or biometric data are recorded, stored, or transmitted. All processing happens locally. You can decline and use the manual slider instead.

Manual Adjustment (Use a tape measure):

50 cm

Calibration Summary

Pixel Pitch—

Distance50 cm

Min Disparity (1 px)—

Testable Range—

Gross Stereopsis Screening

Put on your red-cyan glasses (red lens = right eye). One quadrant contains a raised circle. Tap it.

Level: —″ Trial 1/3

Tap the quadrant with the raised shape

Test Complete

— arcseconds

—

Level-by-Level Results

Disparity	Score	Result

Test Details

Total Trials—

Correct—

Overall Accuracy—

Gross Stereopsis—

Normative Data

3–5 years≤ 100″

6–9 years≤ 60″

10+ / Adult≤ 40″

Evidence Base

Test uses 4AFC random dot stereograms with anaglyph encoding (red-cyan). Descending method of limits with 3 presentations per level (≥2/3 pass criterion), consistent with the Randot Preschool Stereotest methodology.

Scientific Articles:

Bonfanti S, et al. "Evaluation of stereoacuity with a digital mobile application." Graefes Arch Clin Exp Ophthalmol. 2021;259(9):2843-2848. PMC8380567

Tittes J, et al. "Assessment of stereovision with digital testing in adults and children with normal and impaired binocularity." Vision Res. 2019;164:69-82. DOI: 10.1016

Barnett-Itzhaki G, et al. "Evaluating distance stereoacuity in children 4-17 years of age with a novel digital application." J AAPOS. 2024;28(3):103904. DOI: 10.1016

This is a screening tool only. Results do not constitute a medical diagnosis. Please consult an eye care professional for comprehensive assessment.