Widespread clinical adoption of photodynamic therapy (PDT) and photobiomodulation (PBM) has been limited due to the lack of a suitable commercial light source. Cost-effective quantum dot light-emitting diodes (QLEDs) promise to be an ideal light source nicely fitting into this niche, not only complying with desired form factors—flexibility, lightweight, and uniform large area illumination—but with narrow emission spectrum and high power density at clinically relevant deep red wavelengths. This paper is intended to provide a review on the development of QLEDs as a photomedical light source, specifically, for PDT and PBM. First, we introduce the potential of QLEDs as light sources in the photomedical field, briefly describe the mechanisms and benefits of both PDT and PBM phototherapies, and present the unique features of flexible QLEDs (FQLEDs) over conventional and commercial light sources. Then, the pioneering work and state-of-the-art research using QLEDs and organic light emitting diodes (OLEDs) for photomedicine are presented. The performance of QLEDs/OLEDs used in photomedical studies and latest progress on QLEDs are also summarized. Ultimately, we discuss the materials and design strategies for fabrication of efficient and stable FQLEDs, and present the basic requirements for near future introduction of FQLEDs into the healthcare and photomedicine markets. This review is expected to be comprehensive and useful to the scientific community interested in developing lightweight and flexible light sources for photomedicine and/or exploring novel applications for OLED/QLED based lighting devices.
Since their inception, quantum dots have proven to be advantageous for light management applications due to their high brightness and well‐controlled absorption, scattering, and emission properties. As quantum dots become commercially available at large scale, the need for robust, stable, and flexible optical components continues to drive the development of robust and flexible quantum dot composite materials. In this review, after a thorough introduction to quantum dots, discussion delves into methods for fabricating quantum dot loaded composite optical elements such as thin films, microfabricated patterns, and microstructures. The importance of surface chemistry and ligand engineering, host matrixes, wet processing, and unique patterning methodologies is presented by considering photostability, aggregation, and phase separation of quantum dots in corresponding composites. With regard to prospective optical applications of quantum dot materials, emphasis is placed on light emitting and guiding composite materials for lasing applications, specifically whispering gallery mode‐based photonic microsystems. These developments will enable novel flexible, portable, and miniaturized optoelectronic devices such as light‐emitting diodes, flexible pixelated displays, solar cells, large‐area microwaveguides, omnidirectional micromirrors, optical metasurfaces, and directional microlasers.
more » « less- Award ID(s):
- 1803495
- NSF-PAR ID:
- 10462470
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 7
- Issue:
- 4
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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