This is a 12-month longitudinal randomized controlled trial aiming to evaluate the effect of colour temperature of reading lamp on refractive error development.

Myopia has reached epidemic in the world, especially in East Asia. The proportion of myopic population increases drastically during schoolage. Lack of light exposure has been suggested to be a risk for myopia development, in which additional reading lamp may alleviate this condition. However, the effect of colour temperature of the reading lamp is unknown on childhood refractive error development. In this study, investigators will randomly allocate school-aged children into groups, who will receive reading lamps of different colour temperatures for their daily use. The participants' refractive error and axial length will be evaluated.

Inclusion Criteria:

• aged between 4 and 18 years

Exclusion Criteria:

• have received myopia control intervention