LED Based Light Physical Therapy Apparatus For Treating Acne

Phototherapy is characterized by little side effects, painless, significant effects, no pollution and other advantages, meanwhile, it will not leave scars after treatment. In the last century, phototherapy instruments were generally large and had complex operation due to the limitation of the light source, therefore, it was generally difficult to be applied to treat the disease in a family environment. However, at present, with the development of LED technology, the intelligent and portable phototherapy instruments are more and more popular for its small size, long life, energy saving, environmental protection, and other advantages. Furthermore, photodynamic therapy has begun to play an important role in the treatment of various diseases.Acne, as an inflammatory dermatosis of pilosebaceous unit, troubles the people all around the world. There are a variety of methods to treat acne, among which, blue light irradiation with 415 nm wavelength has been proven as an effective treatment method without side effects in clinical trials. There are endless phototherapy products for cosmetic acne in the market, but these products still have some deficiencies, and consumers have a number of negative repercussions for the treatment effects of these instruments. Hence, this paper designs a portable phototherapy instrument against acne on the basis of these deficiencies.In this paper, the optical design of light source used in phototherapy instruments is conducted. In the process of design, arrangement style of LED array can be determined theoretically by using mathematical calculation, so as to make its uniformity of illumination on the target surface at close range can meet the design requirements. After calculating the arrangement style of LED array, simulate test should be conducted by using optical simulation software Tracepro to check whether it can meet the design requirements. After the design of the arrangement style of array and simulation verification, leak-proof light protection cover is also designed. The software modeling is built by Solidworks, and then, input the modeling to Tracepro. Finally, the following conclusion can be reached by adopting optical tracing through Tracepro: The interior leak-proof light protection cover should be designed as parabolic reflective surfaces for maximum utilization of energy emitted by the LED light source and small effect of uniformity of illumination.The drive and control of the LED light source has been designed, among which, all the chips and electronic components have also been screened rigorously. As for the aspect of control, the users can manually adjust the light-emitting area of light source based on their own needs, and thus, the light spot formed by light source on the target surface can be adjusted accordingly. The investigation of clinical trials using LED to treat acne shows that: the required light dosage of blue light irradiation with 415 nm wavelength for acne treatment is 30 m W/cm2, and the treatment time is 15 min. Meanwhile, the performance of model machine has been tested, as a result, it can prove that the instrument has stable performance and the light source has good glowing effect.