196 / 2024-07-09 22:28:32

Digital light processing and optical tweezers: techniques and applications in soft materials

optical manipulation, holographic optical tweezers, digital light processing, microfluidics, spatial light modulator, wavefront-shaping

Optical manipulation technologies such as optical tweezers and associated techniques like optothermal, optoelectronic, have been developed for various applications in biophysics, single molecule analysis, cell and tissue studies, as well as optical manipulation of chemical processes in organisms, lab-on-a-chip development and environmental monitoring.

Among these technologies, optical tweezers, stand out as one of the most widely used methods of optical trapping, operating by harnessing the mechanical effects of the interaction between light and matter. By utilizing a light beam with a specific intensity distribution, optical tweezers can generate a force on the scale of a piconewton, enabling the trapping and manipulation of small particles without causing any mechanical damage. In contrast to traditional single-well optical tweezers, holographic optical tweezers have the capability to create large arrays of trapping sites to capture multiple particles simultaneously. Additionally, they can independently control each trapped particle through computer programming. Holographic optical tweezers utilize the phase-only spatial light modulator (SLM) to shape the wavefront phase of the optical field, enabling the generation of complex optical trapping arrays. The evolution of optical tweezers is progressing towards enhanced performance and a broader range of functionalities with the integration of digital light processing (DLP) technology. DLP powered by a LED or laser source, can generate intricate light field patterns through phase encoding or amplitude modulation. This capability allows for the manipulation of specimens in real time by inducing electronic or thermal field transformations. By leveraging DLP technology, holographic optical tweezers can achieve high-precision manipulation of small particles and perform mechanical measurements. The dynamic light field modulation provided by the DLP system enables holographic optical tweezers to operate in a more flexible and versatile manner. The DLP system can achieve rapid and dynamic modulation of light field, providing more flexible and various operation modes for holographic optical tweezers.

Herein we outline the future prospects of optical manipulation techniques, highlighting their significant potential applications across various scientific disciplines and in everyday practical applications.