Application of Pure Phase Space Optical Modulator in STED Super-Resolution and Holographic Optical Tweezers

Application of Pure Phase Space Optical Modulator in STED Super-Resolution and Holographic Optical Tweezers

I.

Since ordinary optical microscopes are limited by optical diffraction limits, the resolution can only reach about half of the wavelength of visible light, that is, 200-300 nm

Meadowlark Optics focuses on the design, development and manufacture of analog addressable pure phase space optical modulators, with a history of more than 40 years, the company's space optical modulator products are widely used in adaptive optics, scattering or turbid media imaging, two-photon/ three-photon microscopic imaging, optogenetics, holographic tweezers (HOT), pulse shaping, optical encryption, quantum computing, optical communications, turbulence simulation and other fields

Figure 1.

Second, the introduction of the technology of space light modulator in STED super-resolution

Ordinary far-field fluorescence microscopy, using a focused far-field beam of light to irradiate fluorescent molecules, due to the presence of diffraction effects, a limited size of light spot is formed on the sample, and the fluorescent molecules within the spot are all excited and fluorescent

Fluorescent molecules need to be spontaneously fluoresced in the excited state, so the excited state is a bright state, and the ground state of the fluorescent molecule is used as the dark state

Only fluorescent molecules in regions with zero or lower loss of light intensity can return to the excited state in the form of spontaneous radiation to fluoresce, thus achieving a reduction

Figure 2.

Traditional methods can use spiral phase plates to generate such vortex beams, but using pure phase space light modulators to produce such vortex light has greater flexibility

Third, the technical introduction of space light modulator in holographic optical tweezers

Optical tweezers can be used to manipulate particles with different material properties, ranging in size from a dozen nanometers to a dozen microns

Fig.

Traditional optical tweezers typically use beam deflectors, such as scanners or acousto-optic modulators, to achieve multi-particle capture and manipulation

Spatial Light Modulator (SLM), as one of the core devices of holographic optical tweezers, captures and manipulates

Figure 4.
Holographic optical tweezer system

Figure 5.
Dot plot

Fourth, the requirements of the liquid crystal space optical modulator

1.
Light utilization

For optical tweezer applications, the incident optical power affects the power
of particle manipulation.
Therefore, the light utilization rate of the space light modulator is very important, and the light path usually chooses a small angle incidence to improve the light utilization
rate.

Meadowlark offers a 95.
6% spatial light modulator in the SL version with a resolution of 1920x1200, a high refresh rate version of 1024x1024 pixels, a fill factor of 97.
2%, and a dielectric mirror coated version (100% fill rate
).
The SLM version can achieve 100% reflectance, 98% primary diffraction efficiency, and has a high damage threshold to withstand higher power
.

2.
Refresh rate (up to 1K Hz)

The high speed enables real-time manipulation of multiple particles, usually in the infrared range of imaging options, and the Meadowlark SLM is capable of providing a refresh rate
of several hundred hertz at 1064 nm.

3.
Resolution (1920x1200)

High-resolution SLM is ideal for creating the complex phase functions required for 3D positioning, which allows for free regulation
of the light field in each small cell region.

Shanghai Haoliang Optoelectronics, as the general agent of Medowlark in Chinese mainland, provides you with professional selection and technical services
.
If you have any questions or concerns about Meadowlark SLM, you are welcome to contact us
by phone, email or WeChat.

Shanghai Haoliang Optoelectronic Equipment Co.
, Ltd.
is a professional agent of optoelectronic products, including various types of lasers, photoelectric modulators, optical measuring equipment, optical components, etc.
, involving applications covering material processing, optical communications, biomedical, scientific research, national defense, quantum optics, biological microscopy, IoT sensing, laser manufacturing, etc.
; Can provide customers with complete equipment installation, training, hardware development, software development, system integration and other services
.