Line-scanning confocal ophthalmoscope system based on laser diffraction and method

Abstract

The invention relates to a line-scanning confocal ophthalmoscope system based on laser diffraction and a method. The system comprises a linear beam generation module, a beam-splitting module, a scanning module, an imaging module and an output module. The invention is characterized in that: the intensity of the linear beam generated by the line-scanning confocal ophthalmoscope system is uniformly distributed in a non-Gaussian form, a scanning galvanometer is adopted to scan the linear beam in a one-dimensional space to illuminate an ocular fundus retina, meanwhile, a linear detector is used for imaging the non-scanning linear beam reflected by the ocular fundus retina, and since the system only uses one scanning galvanometer and one linear detector, the number of the moving parts is less; meanwhile, a confocal slit is conjugated with the ocular fundus retina plane, consequently, the affection of the stay light of the non-retina plane on the imaging quality is eliminated, and thereby the high resolution of the confocal imaging principle. The system has the advantages of good linear beam quality, simple system structure, easy manufacturing, short light path, easy adjustment, small size, applicability, high stability and high imaging frame frequency.

Description

Technical field [0001] The invention relates to a confocal imaging system and method in the field of optical imaging, in particular to a line scanning confocal ophthalmoscope system and method based on laser diffraction, which can be widely used in biomedical ophthalmology examinations. Background technique [0002] The successful application of confocal scanning technology in imaging has broken through the bottleneck of traditional optical imaging, can obtain high-resolution imaging, and promote the development of optical imaging detection technology. In recent years, scholars have conducted a lot of research on this technology and realized a variety of confocal scanning imaging devices. [0003] The optical principle of confocal scanning technology is as figure 1 As shown, the scanned sample is at the focal plane position of the illumination objective lens while ensuring that the detector is at the focal plane position of the imaging objective lens, that is, at the conjugate posi...

AI Technical Summary

Problems solved by technology

This point-scanning confocal imaging technology has good imaging effect, but it has many defects: (1) There are many optical path components, the optical path is complicated, the system structure is large, and it is inconvenient to use, so it is not suitable for widespread use; And vertical scanning VS two galvanometers, there are many moving parts, it is difficult to control; (3) The light spot energy of point scanning is small, so it needs to use photomultiplier tube PMT or other weak light spot detectors, the obtained image has low contrast, and the frame rate The speed is small (<30fps), so that the retinal jitter image of the intra-frame image cannot be eliminated; (4) the use of point scanning to image the fundus retina usually requires dilated observation and requires the observer to have a good fixation ability. Difficult for eye disease patients, the elderly and children

This device achieves the goal of "quasi" confocal imaging with high resolution, but it still has many defects: (1) it adopts laser point light source for illumination, the light source is complicated to adjust, and the energy distribution of the beam is uneven and Gaussian; (2) For the divergent beam of the point light source, the line beam generating device is composed of two cylindrical lenses, the structure of the line beam generating device is complex, the adjustment is difficult, and the quality of the generated line beam is not good; The energy distribution is uneven, showing a Gaussian distribution. The line beam is focused and diverged many times during the process of propagating to the fundus, and the quality of the line beam is poor; (4) The scanning beam reaching the human eye is orthogonal to the incident beam reaching the scanning galvanometer, The incident beam is scanned after being deflected by the galvanometer by 90 degrees. The scanning method is complex, difficult to control, and has low precision.

Images