System for suppressing zero-order diffracted light of spatial light modulator based on double-plano-convex cylindrical lens

Abstract

The invention discloses a system for suppressing the zero-order diffracted light of a spatial light modulator based on a double-plano-convex cylindrical lens. A laser emits laser, the laser enters a half-wave plate after being expanded by a 4F system, enters a reflecting mirror, enters an aperture after being expanded by the 4F system after being reflected, and then enters a polarizing film; a light beam transmitted by the polarizing film passes through an axis orthogonal double-plano-convex cylindrical lens combination and then enters a liquid crystal spatial light modulator; after modulation, the light is reflected back to the axis orthogonal double-plano-convex cylindrical lens combination for transmission, enters the 4F system for beam expansion and is transmitted to be focused and imaged by a front objective lens, and an image is received by a CCD camera after being amplified by a rear objective lens and a tube lens. The technical problem that zero-order diffracted light modulatedby the spatial light modulator is focused into a zero-order diffracted light spot on an image plane is solved, the influence of the zero-order diffracted light spot on the image plane is eliminated,and the system has the advantages of being wide in application range, not prone to damage a sample in the imaging process, high in compatibility and fault-tolerant capacity and the like.

Description

technical field [0001] The invention relates to a spatial light modulation diffracted light system and method in the field of optical imaging, in particular to a system for suppressing zero-order diffracted light of a spatial light modulator based on a biplanar-convex cylindrical lens. Background technique [0002] A spatial light modulator is an optical device that can be controlled by a computer to impose some form of spatial variation on a light beam. This variation can be phase modulation or intensity modulation, or polarization state conversion. The spatial light modulator is a plurality of independent units arranged regularly, and each unit can independently receive the control of optical signals or electrical signals, and use physical effects such as the Pockels effect, acousto-optic effect, and magneto-optical effect to change its own optical characteristics and realize The corresponding modulation of light waves incident on the modulator. The light beam incident on...

AI Technical Summary

Problems solved by technology

[0005] Although the first method can effectively remove zero-order diffracted light, and can ensure that the resolution and signal-to-noise ratio of the target image plane do not change significantly, it will introduce a blind area in the imaging field of view, although the blind area can be adjusted by moving the stage imaging, but doing so can damage the sample and increase scan time

[0006] The second method is to shift the focal position of the high-diffraction order axially away from the focal plane of the objective lens, but the diffraction efficiency of the off-focus plane is very low, which will greatly reduce the image signal-to-noise ratio

[0007] The third method uses a combination of concave-planar-convex cylindrical lenses orthogonal to the axis, so the zero-order diffracted light will be focused into two focal lines on both sides of the image plane. This method limits the three-dimensional holographic imaging to a certain extent. Axial size

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