Auto-Lux-Adaptive Pupil-Adjustment Glasses

Haowei. Jiang, #5016-6365, haoweiji@buffalo.edu

EE526LEC000: Wearable & Implantable Sensors, Department of Electrical Engineering,

University at Buffalo, The State University of New York (SUNY at Buffalo), Buffalo, New York 14260, USA

Background: By applying the circular filter plate, the polarization effect can be secured in the glasses. A color-

sensitive, UV-blocking lenses can be additively inter-laced with silver-halide polymer to achieve a better eye-

comfort under exposure to high actinic radiation [1]. Interference films could also be surface-layered to generate the

iridescent effect which is visible to outsiders but wearers [2]. A new method, ALAPA, is proposed to improve the

overall adaptiveness to sudden lightness change based on external LUX and pupil size.

Working Principle/Design: The work-flow schematic is shown in (Fig. 1). The pupil dilates/shrinks when exposed

to dark/ high light intensity environment. The diameter difference is tracked by the embedded pinhole camera using

eye/pupil detection method [3] (Fig. 2 & Fig. 3). At the meantime, the external LUX is detected by ALS (Automatic

LUX Sensor) and then sent to adjust the angle of circular polarizer (rotatable & controlled by CPU, the larger angle

is, the less LUX passing through) together with the transformed pupil sense message (which also functions as a

compensatory signal to the liquid crystal layer), allowing certain amount of LUX passing through and reach the

pupil end to ensure a relatively stable pupil size under pre-set-able LUX environment. (Fig. 4) demonstrates the

lenses layer deign.

Expected Outcomes/Impacts: we pre-set the LUX parameter (80 LUX - level 6 - toilet lighting) by pressing the

LUX-lock button when the tester’s pupils are adaptive to test environment (the initial diameter is about 4mm with

pre-set LUX). The LUX level-step curve shows on (Fig. 5). In the Blank setting, we trace both left & right pupil

diameter change following the LUX curve without ALAPA glasses, with it in the experiment group. When it comes

to the comparison (Fig. 6), we find that both left & right pupil get narrow as LUX level goes up in the blank group.

While in the experiment set, there are just a little variation according to the diameter change and its value is

stabilized around 4mm with no 10% error range exceeding.

We could also refer to the angle change of circular polarizer and luminance compensation from the liquid crystal

layer (Fig. 7) that the angle is proportional to the LUX level which follows the working principles and the

compensation mechanism only works as the LUX level goes higher than level-8, generating a LUX level down

voltage signal to liquid crystal layer, changing its transmittance.

Conclusion: we have figured out an achievable way to adjust the human pupil size matched comfort light

surroundings using the pupil detection & adaptive polarization. This design will be health-oriented for those who

suffer extreme light changes and back for the growing fashion.

Word Count: 441

[1] Joseph E. Pierson, Stanley D. Stookey, 1976. Method for Making Photosensitive Colored Glasses. US736,517.

[2] Michael Black, Vladimir Kupershmidt, 1991. Liquid Crystal Sunglasses with Selectively Color Adjustable

lenses. US640,042.

[3] Cho C. W, Lee J. W, Lee E. C, Park K. R, A Robust Gaze Tracking Method by Using Frontal Viewing and

Eye Tracking Camera. Optical Engineering, 2009, 48: 127202-127202-15.

Fig. 2 Overall Procedure of the proposed eye/pupil

detection method [3] .

Fig. 1 ALAPA Work-Flow Schematic.

Fig. 4 Layers Structure. (From right to left - incident light

direction) Liquid Crystal surfaced with Interference Film

→ Silver Halide Polymer → Linear Polarizer + Quarter

Wave Plate (Circular Polarizer).

Fig. 5 LUX Level-step Curve in logarithms.

Fig. 6 Left & Right Pupil Diameter Comparison.

Fig. 7 Angle change of circular polarizer and luminance

compensation from the liquid crystal layer

Fig. 3 ALAPA Glasses model with pinhole camera in

the center.