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Effects of Blue-light Blocking Lens on Visual Functions

T

The Hong Kong Polytechnic University

Status

Completed

Conditions

Effects of Blue-light Blocking Lens on Visual Functions

Treatments

Device: regular coating lens with yellow tint
Device: clear lens with regular coating
Device: clear lens with blue-light blocking coating

Study type

Interventional

Funder types

Other

Identifiers

NCT02821403
HSEARS20140512001-03

Details and patient eligibility

About

Working Hypothesis: The blue-light blocking lens has no effect on the contrast sensitivity, accommodative response, color vision, and subjective grading of the quality of life and vision.

Purpose: To determine and compare the visual performances after wearing the blue-light blocking lenses in participants with and without presbyopia.

Methods: One hundred and sixty computer users (computer usage >2 hours/day) with (n=120, aged >40years) and without presbyopia (n=40, aged 18-35 years) will be recruited. Three pairs of ophthalmic lenses will be prescribed for the participants, in which one pair of them will be the blue-light blocking lenses (StressFree, Swisscoat, HK). The lenses will be used for intermediate vision (i.e., computer usage) in presbyopic group, and for distant vision in non-presbyopic group. The adaptation period for each pair of lenses will be 1 month. The pre- and post-treatment contrast sensitivity, accommodative response and color vision will be measured. The participants will also be asked to complete questionnaires about their quality of life and vision, and the performances of these ophthalmic lenses.

Significance: The blue-light blocking lens reflects the short-wavelength lights and protects the retina from "blue-light hazards"; however, blue lights are essential for various visual function and circadian rhythms. This study will evaluate the impact of the blue-light blocking lenses on visual function and quality of life, and determine whether the blue-light blocking lenses are good choices for extra ocular protection.

Enrollment

80 patients

Sex

All

Ages

18 to 55 years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

  • age: 18 to 35 years OR 40 to 55 years
  • daily computer usage over over 2 hours per day

Exclusion criteria

  • visual acuity worst than 0 logMAR
  • abnormal binocular and color vision
  • previous history of ocular surgeries

Trial design

Primary purpose

Other

Allocation

Non-Randomized

Interventional model

Parallel Assignment

Masking

Single Blind

80 participants in 2 patient groups

Young adults
Experimental group
Description:
adults without presbyopia who aged 18-35 years
Treatment:
Device: regular coating lens with yellow tint
Device: clear lens with regular coating
Device: clear lens with blue-light blocking coating
Middle-aged adults
Experimental group
Description:
adults with presbyopia who aged over 40 years
Treatment:
Device: regular coating lens with yellow tint
Device: clear lens with regular coating
Device: clear lens with blue-light blocking coating

Trial contacts and locations

0

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Data sourced from clinicaltrials.gov

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