A New Concept of Binocular Open-view Visual Acuity Test


For some time we have used a clinical visual acuity test (subjective refraction) only for monocular testing. However, we believe that visual acuity measurements need to be performed under binocular open-view conditions as close to natural viewing conditions as possible.

Subjective refractions without cycloplegia were examined with BLOO (the product name is “Occlupad” in Japan), which modified a tablet device to create a binocular open-view visual acuity test device that would only display images that can be seen by one eye with a polarized lens. BLOO can display the Landolt-C chart on the monitor. To create BLOO, we removed only the polarizing film layer from the liquid crystal display (LCD) screen of a tablet. Thus, unless a subject viewed the screen using a circular polarizing lens, the LCD screen only appeared to produce a white backlight. Designing the polarizing filter to exactly match the polarization meant visual information could only be perceived by a human eye.

We are pleased to announce that our study has been published in Healio.com. For more information about this topic, please see the study linked below.



Tomoya Handa
Nobuyuki Shoji
Kimiya Shimizu

From Kitasato University, Japan


Published on Healio.com