Afterimage therapy is a common method of amblyopia treatment. It is designed based on the principle that the human retina can form a posterior image after being irradiated by bright light, and the process of producing the posterior image can improve vision by removing the inhibition in the macular area of the fundus to varying degrees. The effect is twofold: correction of eccentric fixation and improvement of visual acuity. The rear image mirror is created on the basis of direct pick-up glasses. It protects the central recess by distributing 3°, 5°, and 7° black dots in the center of the 30° range of bright light, and the retina around the 30° range of bright light stimulation will show a momentary decrease in function, including the eccentric fixation point, but because the central recess has been protected by the black dots and not stimulated by bright light, the central recess function is relatively improved under induction light. The method is to dilate the amblyopic eye and make the fixated eye look at a distant target to ensure that the fixated eye does not move during treatment. In the case of eccentric fixation, a fixation target can be set in front of the fixated eye and every effort is made to keep the fixated eye from moving. The examiner irradiates the base of the amblyopic eye in a dark (semi-dark) room with a posterior mirror, so that the black dot shadow falls on the central concave area to protect the central concave, and irradiates with a strong light (6V, 15W) for 20 to 30 seconds. If the fixation ability is poor or there is nystagmus, irradiation can be performed with the posterior mirror following the central concavity. After irradiation, cover the healthy eye and ask the patient to look at the crossed visual markers in the center of the white screen and ask if the posterior image appears. What is the duration of the posterior image? What is the relationship between the posterior image and the crosshair? The duration of the posterior image can indicate the degree of amblyopia, and it is difficult to produce the posterior image in high amblyopia. The central sulcus is stimulated by the posterior image method, so that its function is in a superior state than the peripheral part, forming a forced recovery function, and also the position of the posterior image can make it perceive the correct direction of the visual space. For eccentric gaze, spatial gaze training can be conducted to re-establish the physiological direction of gaze and central fixation, and brain, hand and eye coordination spatial perception training and central fixation training can be conducted as follows: after self-awareness of the posterior image, the patient is instructed to point out the position of the posterior image on the white screen 30 cm in front of him/her with an indicator stick and to move to the center of the cross on the white screen, i.e., the self-awareness of the line of sight is trained to return to the central recess outside the central fossa. The spatial position training is performed to correct the eccentric gaze, and the distance can be increased afterwards to strengthen the effect. Sometimes monocular diplopia may occur temporarily, which is a struggle between the old and new fixation points until the new fixation point becomes dominant. After restoring the spatial perception of the central macular sulcus, we can continue to improve the central vision training, i.e., vision enhancement therapy: after the formation of the afterimage, we can gaze at the visual acuity meter and use the point day adjustment device to irradiate the point day to prolong the afterimage. The procedure was repeated 2 to 3 times a day (about 30 minutes each time) after the afterimage disappeared. When the visual acuity reaches 0.3m or higher, both eyes should be trained at the same time to improve visual function. In amblyopia with central synoptic vision, visual acuity improves faster, while eccentric fixation visual acuity improves worse. 4. Unstable type: The improvement of visual acuity is unstable, often changing with the change of gaze status.