---
title: 2.5 PLR Video Mode – Android
description: "PLR (Pupillary Light Reflex) video mode records the pupil's response to a light stimulus, allowing measurement of constriction speed and amplitude over time. ****When to use**** Use PLR mode when you need to assess neurological pupil response, not just static…"
url: "https://cnri.edu/docs/2-5-plr-video-mode-android/"
updated: "2026-03-24"
category: Capturing Eye Images
---

# 2.5 PLR Video Mode – Android

PLR (Pupillary Light Reflex) video mode records the pupil's response to a light stimulus, allowing measurement of constriction speed and amplitude over time.

****When to use****

Use PLR mode when you need to assess neurological pupil response, not just static iris morphology.

****How to capture****

1. Select ****PLR Video**** from the Camera Mode Selector.

2. Choose front or rear camera and which eye.

3. Ensure the room is dim before starting.

4. Tap ****Record**** — a light stimulus is presented on-screen or externally.

5. The pupil constriction/dilation cycle is recorded and analyzed frame-by-frame.

PLR results appear on a separate results screen and are not combined with the standard iris analysis or windows version.