Journal of Dermatological Science.
VOLUME 101, ISSUE 2, P138-140, FEBRUARY,2021 

Ultraviolet A1 phototherapy utilizing ultraviolet light-emitting diodes and a short wavelength cutoff filter 


Hideyuki Masuda1,2, Akimichi Morita1 

1 Department of Geriatric and Environmental Dermatology, Nagoya City University, Graduate School of Medical Sciences, Nagoya, Japan 

2 USHIO INC, Tokyo, Japan 




 UVA is divided into UVA1 (340-400 nm) and UVA2 (320-340 nm). UVA2 has similar characteristics to UVB, such as inducing erythema, etc. Treatment using UVA1 requires a relatively higher irradiation dose than treatment using UVB. UVA1 therapy is characterized by its ability to reach deeper into the skin than UVB. Therefore, it is effective for diseases with dermal etiology (atopic dermatitis, cutaneous T-cell lymphoma, prurigo, scleroderma, etc.). Traditionally, lamps have been used as the light source, but LEDs have been desired for their high efficiency and long life. However, since LEDs and lamps have different spectra, experiments using cells were conducted to clarify the optimal wavelength characteristics. 




Copyright © USHIO INC. All Rights Reserved