This double-blind, randomized controlled clinical study is to evaluate the effectiveness and safety of low concentration atropine in preventing myopia in pre-myopia children, and to explore whether there is a dose effect relationship between different concentrations of atropine in preventing myopia.

The main questions this double-blind, randomized controlled clinical study aims to answer are:

1. To evaluate the effect of low concentration atropine on the incidence of myopia in pre myopia children.
2. To evaluate the effectiveness of low concentration atropine in controlling refractive and axial progression.

Patients are randomly divided into three treatment groups with different atropine concentrations(0.01%, 0.02%, 0.04%) and one control group with atropine dissolvant. Patients are required to use the eye drops every night for one year and record after daily usage.

Inclusion Criteria:

1. The age of the screening stage is 6-9 years, both sexes;
2. One eye met the diagnosis of pre-myopia, the spherical equivalent was between -0.50D and +0.75D, the astigmatism was ≥-1.50D, and the best corrected far vision was at least 1.0;
3. At least one of parents suffers from myopia (SE of at least one eye <=-3.00D);
4. Parents have signed informed consent and agree to participate in screening and follow-up.

Exclusion Criteria:

1. Parents disagree to sign the informed consent;
2. Presence of strabismus, amblyopia, or other ocular abnormalities, or have a history of eye surgery;
3. Presence of other eye or systemic diseases;
4. Allergies to low concentration atropine or sulfuric acid drugs;
5. Histories of using other preventive measures, such as using red light within 6 months or atropine within 1 month;
6. Presence of other situations that the researchers think is not appropriate for patients to be included in the project.