Minimum Power and Frequency of Repeated Low-level Red-light to Effectively Control Myopia Progression

Inclusion Criteria: 1. Age: 8-10 years old 2. Low myopia: cycloplegic spherical equivalent refractions (SERs) range from -0.50 (inclusive) to -3.00 diopters (D) and astigmatism less than -2.5 D in either eye. 3. signed informed consent and was able to participate in the study Exclusion Criteria: 1. Secondary myopia, such as a history of retinopathy of prematurity or other neonatal diseases; syndromic myopia with a known genetic disorder or connective tissue disease, such as Stickler syndrome or Marfan syndrome 2. Strabismus or other binocular vision abnormalities 3. Cloudy refractive media: cloudy cornea, cataract or intraocular lens surgery 4. Eye diseases that affect retinal function: macular degeneration, diabetic retinopathy, retinal detachment, glaucoma or ocular hypertension, endophthalmitis, uveitis, optic neuropathy, etc. 5. History of refractive surgery, internal eye surgery, laser therapy, vitreous injection, etc. 6. diabetes, hypertension and other systemic disorders 7. History of use of retinal toxic drugs, such as hydroxychloroquine, etc. 8. Use of orthokeratology, atropine, multifocal frame glasses and other myopia control methods; children who are currently receiving atropine, orthokeratology, multifocal frame glasses and other myopia control treatment, can be enrolled after 2 weeks of treatment. 9. Other reasons considered unsuitable for inclusion by the study physician, including but not limited to other ocular and systemic disease abnormalities