Antifungal effects of ultraviolet C (UV-C) irradiation have been considered a potential solution to reduce the severity of black spots on postharvest fruits. In this work, a 30 × 30 × 30 cm system was made based on UV-C light-emitting diodes (LEDs) to apply in reducing disease symptoms for bananas which could be used in industrial conveyor belts. The UV-C irradiance monitoring was carefully carried out for several sections at various box heights in simulation and measurement. The findings experienced a dominating range of 6 to 9 W/m2 in the central sections. Regarding in vivo conditions, the observation after a week from experiment showed that the disease symptoms on the UVC-treated banana peel, which was exposed under UV-C light around 5 s, dramatically decreased compared to a natural banana. Consequently, the UV-C dose range is proposed from 0.030 to 0.045 kJ/m2 with minimum damage in terms of sensory properties. Owing to the flexible shape and short exposure time, the system promises to provide many potential applications to prolong the quality of bananas.
We perform the mid-field model of a UV-C LED with an arranged wavelength of around 275 nm by comparing the 2-dimension (2-D) gray-level image captured by a monochromatic CMOS and the corresponding simulated irradiance pattern. Owing to UV-C light, we propose using a fluorescent film to absorb UV-C light and re-emit light at a longer wavelength so that the 2-D gray level image can be captured. The calibration to approach the corrected gray level of image is presented. Consequently, we obtain the precise mid-field light source model. Moreover, the model is also applied for dome lens design and then compares the optical behavior with fabricated samples in measurement to evaluate its validity.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.