Effect of Yellow Light AG Mobile Phone Screen on Dry Eye and Asthenopia.

NCT07340359 | Completed

• 1 other identifier: 2025-1513
• Study Type: interventional
• Target: 70
• Locations: 1 country
• Sites: 1

Brief Summary

This study aimed to evaluate the protective effects of yellow-light etching anti-glare (AG) screen on Digital Eye Strain (DES) induced by prolonged video display terminal (VDT) use under dim environment, Based on the proved positive effect of the circular polarization (CP) screen, providing insights for new eye-protection strategy in the highly digital modern era. In a randomized, double-blind controlled trial, 70 eligible volunteers (diopter ≤ -6.0D; anisometropia ≤ 2.0D) were divided into AG+CP or CP only groups. Participants performed a 2-hour e-book reading task using assigned AG+CP or CP only smartphones. Subjects' severity of DES pre- and post-reading were evaluated from two aspects: the degree of dry eye symptoms and asthenopia. Dry eye symptoms indicators (OSDI, TMH, NIBUT, FBUT, CFS, Schirmer I Test) and asthenopia indicators (CVSS17, Bulbar redness, HFC) were measured and compared.

Conditions

Digital Eye Strain; Computer Vision Syndrome; Dry Eye; Asthenopia

Outcome Measures

Primary Outcomes (3)

• Flourescence tear break-up time

  Drop a drop of physiological saline onto a sodium fluorescein test strip. Gently touch the middle of the conjunctiva of both lower eyelids of the examinee with the test strip respectively, and instruct the examinee to blink their eyes gently and look straight ahead. The examiner observed the tear film of the examinee with cobalt blue light under a slit lamp. The time of tear film rupture was the time from the examinee opening their eyes to the appearance of the first black spot on the tear film. Three TBUT tests were detected and recorded for each eye respectively, and the average and maximum values were taken.

  1 month

• HFC (high frequency component of accommodative fluctuation)

  The SCR mode of the ACOMOREF K-MODEL computerized optometer was adopted. The subjects were asked to keep a close eye on the image. The image distance was gradually moved from infinity to 1m, 60cm, and 30cm, and remained at each of the four distances for 20 seconds. The equipment would analyze and record the high-frequency fluctuations of the subjects' ciliary muscles, known as HFC. After the test of the first eye, Take a 20-second break to test the second eye.

  1 month

• non-invasive tear break-up time

  The Oculus ocular surface comprehensive analyzer was adopted. The examinees sat upright in front of the instrument and were asked to blink their eyes lightly and then look at the red marked object. The instrument automatically conducted ocular surface image analysis to obtain and record the first NIBUT and average NIBUT of the examinees

  1 month

Secondary Outcomes (4)

• tear meniscus height

  1 month

• corneal fluorescein staining

  1 month

• computer vision symptom scale 17

  1 month

• Schirmer I test

  1 month

Study Arms (2)

yellow light AG group

EXPERIMENTAL

use yellow light AG smartphone

Behavioral: reading 2h on smartphone

control group

PLACEBO COMPARATOR

use non-yellow light AG smartphone

Behavioral: reading 2h on smartphone

Interventions

reading 2h on smartphone BEHAVIORAL

reading 2h on smartphone

control group; yellow light AG group

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• have basic reading comprehension skills and to be older than 18 years old. 2.diopter of both eyes not exceeding -6.0D and anisometropia not exceeding 2.0D.

You may not qualify if:

• presbyopia or decreased regulation function, 2.ocular inflammation and disease, 3.worn contact lens within 1 month, 4.history of eye surgery within 6 months, 5.lactating or pregnant woman, 6.have severe systemic diseases.

Sponsors & Collaborators

• Second Affiliated Hospital, School of Medicine, Zhejiang University: lead

Study Sites (1)

The Second Affiliated Hospital Zhejiang University School of Medicine (SAHZU)

Hangzhou, Zhejiang, 310000, China

Location

MeSH Terms

Conditions

Dry Eye Syndromes; Asthenopia

Condition Hierarchy (Ancestors)

Lacrimal Apparatus Diseases; Eye Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 6, 2026
• First Posted: January 14, 2026
• Study Start: January 10, 2026
• Primary Completion: January 21, 2026
• Study Completion: February 21, 2026
• Last Updated: March 5, 2026

Record last verified: 2025-12

Locations

CN (1)