Area array detection type stimulated radiation loss imaging system

Abstract

An area array detection stimulated radiation depletion imaging system, including an excitation light source for generating excitation light, a depletion light source for generating depletion light, a beam expander system, a vortex phase modulation plate, a dichromatic mirror, and a wave plate , scanning galvanometer, scanning lens, tube lens, objective lens, nano-shift stage, telephoto converging lens and area array detector, the excitation light after beam expansion by the beam expander system and the beam expander system, vortex phase The lost light after beam expansion and phase modulation by the modulation plate enters the dichroic mirror and then enters the wave plate. After scanning the lens, tube lens and objective lens, focus on the inside of the sample at the nano-shift stage, and the optical signal generated by the excitation light and loss light focused on the inside of the sample at the nano-shift stage passes through the detection optical path and the telephoto converging lens Converged on the area array detector for imaging. The application is simple and convenient to operate and has high utilization rate of light energy.

Description

technical field [0001] The present application relates to the field of super-resolution fluorescence microscopy imaging. Background technique [0002] The resolution of traditional far-field optical microscopy is mainly limited by the diffraction limit, and the focal point formed at the focal point of the objective lens, that is, the point spread function (PSF), determines its resolving power. Stimulated emission depletion (STED) imaging technology is a far-field optical super-resolution imaging technology, which breaks through the limitation of traditional optical diffraction limit and improves the far-field optical resolution to 50nm or even higher. [0003] The principle of stimulated radiation depletion imaging is to use two lasers with different wavelengths. One laser is called excitation light, which is used to excite fluorescent substances in biological and other samples to an excited state, thereby emitting detectable fluorescence; the other laser is called depleted ...

AI Technical Summary

Problems solved by technology

The point detection system cannot monitor the degree of overlapping of the two lasers in real time. Generally, it is necessary to image the gold particles and detect the PSF of the two lasers separately for precise beam combination. Before the actual sample is imaged, it needs to be replaced with a gold particle sample, and the gold particle The particle sample is repeatedly scanned and imaged to determine the relative position of the two lasers and to adjust them precisely. The operation process is extremely complicated.

In addition, if the position of the pinhole in the system deviates from the main optical axis, the signal strength will also drop sharply. Therefore, it is necessary to keep the height of the pinhole coincident with the main optical axis. However, since the diameter of the pinhole is only 1 times the size of the Airy disk (50- 100 microns), it is easy to deviate due to mechanical and other reasons, resulting in a decrease in the imaging quality of the system, and the position of the pinhole needs to be adjusted before each imaging, which increases the complexity of the operation

[0007] Energy loss: Stimulated radiation loss belongs to low-light imaging, the signal value is very low, and a pinhole with a size of 1 times the Airy disk will prevent the passage of fluorescence in space, resulting in a further decline in light energy utilization, which is not conducive to low-light detection , seriously affecting the image quality

[0008] The detection point spread function is fixed: if a pinhole detector is used in the system, the detection point spread function of the system is fixed, there is no room for adjustment, and it is impossible to start from the detection point spread function to improve the imaging quality of stimulated radiation loss

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