To evaluate the long-term efficacy of repeated low-level red-light (RLRL) therapy in the prevention and control of myopia in children, and to analyze the key factors influencing its efficacy (such as individual differences and compliance), with the aim of providing evidence-based support for the optimization of clinical myopia prevention and control strategies.

This is a real world multi-centre study. The devices are connected to the internet with an automated diary function to record treatment sessions and to monitor patient compliance.The total sample size of 3000 arerandomly allocated into treatment groups,observation for 1 year and more.

Inclusion Criteria:

1. Ages 5 to 16, gender unrestricted;
2. RLRL device usage duration of one year or more.

Exclusion Criteria:

• Children with obvious strabismus and amblyopia
• With congenital eye disease, such as congenital cataract, congenital retinal disease
• Secondary myopia (such as premature retinopathy or other eye diseases in infants and children caused secondary myopia), or myopia combined with systemic syndrome (such as Marfan syndrome)
• Had internal eye surgery (such as cataract extraction, intraocular lens implantation, anti-glaucoma surgery, etc.)
• Refractive medium opacity (such as corneal disease, crystal opacity, etc.)
• Bnormal intraocular pressure and clinical significance (IOP <10 mmHg or IOP >21mmHg or binocular IOP difference ≥5mmHg)
• Fundus chorioretinopathy (except for high myopia fundus degenerative changes) or other intraocular diseases
• Optic nerve damage or congenital optic nerve dysfunction
• Can not be regularly checked
• The adjustment range is less than 8D or obvious near difficulties
• Other reasons researchers think it is not suitable for inclusion in researchers

5-16 years old, 500