CN1300563C

CN1300563C - Minisize three-dimensional self-scanning confocal microscope

Info

Publication number: CN1300563C
Application number: CNB2005100184294A
Authority: CN
Inventors: 张新宝
Original assignee: Huazhong University of Science and Technology
Current assignee: Huazhong University of Science and Technology
Priority date: 2005-03-24
Filing date: 2005-03-24
Publication date: 2007-02-14
Anticipated expiration: 2025-03-24
Also published as: CN1664558A

Abstract

The present invention discloses a miniature three-dimensional self-scanning confocal microscope. A double-comb linear scanner is composed of an actor, an X direction linear driver and a Z direction linear driver which are used as two stators, wherein a second microlens is arranged on the actor; light emitted by a spot type light source becomes a collimated laser beam after passing through a first microlens; after the collimated laser beam penetrates through a miniature optical beam splitter and is reflected by a micro scanning reflector, the beam is focused on a sample by the second microlens; after reflected light or fluorescent light is orderly reflected by the second microlens and the micro scanning reflector along an original optical path, the light returns to the miniature optical beam splitter; the light reflected by the miniature optical beam splitter is irradiated to a miniature optical detector through a third microlens and a pin hole; a control device is used for data acquisition and processing, and controls the double-comb linear scanner to scan in the linear of focal points in X and Y directions. The present invention has the characteristics of small volume, simple structure, good stability, high frequency response of dynamic characteristics and direct three-dimensional solid self-scanning measurement.

Description

Miniature three-dimensional self-scanning confocal microscope

Technical Field

The invention belongs to the technical field of detection, and particularly relates to a miniature three-dimensional self-scanning confocal microscope.

Background

Confocal microscopes have found widespread use in biomedical research as a powerful imaging analysis tool for translucent biological samples, including cells and tissues. In addition, it is widely used for non-contact measurement and research of microfabricated and various engineered surfaces, and vision of autonomous micro-robots. In recent years, researchers have conducted a great deal of research on this technique, and have mainly focused on conventional confocal microscopes.

Confocal microscopes in the laser single-point scanning mode or in the disk-conjugate lattice scanning mode are proposed in "Confocal optical microscopy" (see Rep. prog. Phys.1996, 59: 427-471). The three-dimensional measurement technology usually adopts a two-dimensional layer scanning mechanism and a one-dimensional vertical feeding mechanism to realize the measurement of a plurality of two-dimensional layers so as to reconstruct three-dimensional characteristics. The measurement technology has remarkable effect, but the structure is large, the frequency response of the dynamic characteristic is low, the application of the measurement technology is limited, and particularly the direct application of the measurement technology in a living body is prevented. In addition, the scanning mechanism of the method is complex, and the influence of vibration limits the improvement of the measurement precision and speed, so that the method is not suitable for the requirement of the current rapid online detection.

"Stacked two-dimensional Micro-lens scanner for Micro-confocal scanning array" (see [ 2 ] Micro Electro Mechanical Systems, 2002. Fiftenth IEEE International Conference: 483-486) two-dimensional linearly driven, positioned Micro-scanning lens mechanisms were used for arrays of confocal scanning microscopes to achieve two-dimensional scanning.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a miniature three-dimensional self-scanning confocal microscope. The miniature three-dimensional self-scanning confocal microscope has the characteristics of small volume, high frequency response of dynamic characteristics and direct three-dimensional self-scanning measurement.

The invention provides a miniature three-dimensional self-scanning confocal microscope, which comprises a point type light source, three micro lenses, a micro optical beam splitter, a micro scanning reflector, a double comb-shaped linear scanner, a pinhole, a miniature optical detector and a control device, wherein the point type light source is arranged on the micro scanning reflector; the double-comb linear scanner comprises a rotor, two X-direction linear drivers and a Z-direction linear driver, wherein the X-direction linear drivers and the Z-direction linear drivers are used as stators; light emitted by the point light source becomes a collimated laser beam after passing through the first micro lens; the collimated laser beam penetrates through the micro optical beam splitter, is reflected by the micro scanning reflector and is focused on the sample by the second micro lens; the reflected light or the fluorescence returns to the micro optical beam splitter after sequentially passing through the second micro lens and the micro scanning reflector along the original light path, and the light reflected by the micro optical beam splitter irradiates the micro optical detector through the third micro lens and the pinhole and is converted into a photoelectric signal to be transmitted to the control device; the control device controls the micro-scanning mirror to deflect and scan, and focal point scanning in the Y direction is formed on the focal plane of the second micro lens; the control device controls the X-direction linear driver to drive the rotor clamping the micro lens to form X-direction focus linear scanning; the control device controls the Z-direction linear driver to drive the rotor clamping the micro lens to form Z-direction focus linear scanning; the control device acquires and processes the three-dimensional scanning signals to obtain position signals of the three corresponding directions of the space points; the micro light detector obtains the light intensity signals of the corresponding space points and transmits the light intensity signals to the control device, and the control device obtains the light intensity signals and the corresponding position signal sets.

The invention adopts a micro-scanning reflector, a double comb-shaped linear scanner moving along the mutually vertical direction and an objective lens driving a micro lens to realize direct three-dimensional self-scanning. Meanwhile, the invention utilizes the technology of a Micro Electro Mechanical System (MEMS), and compactly integrates MEMS devices such as a laser source, a micro optical device, a micro scanner, a micro optical detector and the like on the basis of keeping the advantages of high measurement resolution and non-contact measurement of the confocal microscope, and has the characteristics of small volume, high dynamic characteristic frequency response, direct three-dimensional self-scanning measurement and the like, thereby solving the problems of large structure and low dynamic characteristic frequency response of the conventional confocal microscope; the invention also has the characteristics of simple structure, simple and convenient manufacture and good stability.

Compared with a two-dimensional scanning method of a double-microlens, the miniature three-dimensional self-scanning confocal microscope not only has the three-dimensional self-scanning capability, but also has the characteristics of short optical path and simplicity, and further can integrate the detector part of the miniature three-dimensional scanning self-confocal microscope into a size of 2mm level under the condition of minimum noise. Because the mass of the moving part is very small, the working limit frequency of the three-dimensional scanning is more than 1 kHz.

Drawings

Fig. 1 is a schematic structural diagram of a miniature three-dimensional self-scanning confocal microscope.

Fig. 2 is a schematic control principle diagram of a miniature three-dimensional self-scanning confocal microscope.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

As shown in fig. 1, the micro three-dimensional self-scanning confocal microscope includes a point light source 1, a first microlens 2, a micro optical beam splitter 3, a micro three-dimensional self-scanner, a third microlens 10, a pinhole 11, a micro light detector 12 and a control device 13.

The micro three-dimensional self-scanner comprises a micro scanning reflector 4, a second micro lens 5 and a double comb-shaped linear scanner. The double-comb linear scanner is composed of a rotor 6, two X-direction linear drivers 7 and a Z-direction linear driver 8, the X-direction linear drivers 7 and the Z-direction linear drivers 8 serve as stators, the second micro lens 5 is located on the rotor 6, the X-direction linear drivers 7 are used for driving the rotor 6 to move along the X direction, and the Z-direction linear drivers 8 are used for driving the rotor 6 to move along the Z direction.

The point light source 1 may be a micro point laser or a micro point laser diode.

Light emitted from the point light source 1 passes through the first microlens 2 and becomes a collimated laser beam. The collimated laser beam passes through the micro optical beam splitter 3, is reflected by the micro scanning mirror 4, and is focused on the sample 9 by the second micro lens 5. The reflected light or the fluorescence is reflected by the second micro lens 5 and the micro scanning mirror 4 along the original optical path and then returns to the micro optical beam splitter 3. The light reflected by the micro optical beam splitter 3 passes through the third micro lens 10 and the pinhole 11, and after the influence of the defocused light is eliminated by the third micro lens 10 and the pinhole 11, the light irradiates the micro light detector 12, is converted into a photoelectric signal and is transmitted to the control device 13, so that a light signal of a space point is obtained, and the signal of the light intensity is highly localized (corresponding to the space point).

The control device 13 is used for controlling the three-dimensional scanning of the micro three-dimensional self-scanner and is responsible for acquiring and processing the position signal (i.e. the position signal scanned by the micro three-dimensional self-scanner) and the light intensity signal (i.e. the signal from the micro light detector 12) of the three-dimensional scanning. Specifically, the control device 13 controls the micro-scanning mirror 4 to perform deflection scanning to form focus scanning in the Y direction; the control device 13 controls the X-direction linear actuator 7 to drive the mover 6 holding the microlens 5 therebetween, thereby forming a focal linear scan in the X-direction; the control device 13 controls the Z-direction linear actuator 8 to drive the mover holding the micro lens 5 therebetween to form a focal linear scan in the Z-direction, thereby enabling the micro three-dimensional self-scanning confocal microscope to realize a three-dimensional grid type stereo scan of one microchannel. The control device 13 acquires and processes the three-dimensional scanning signals to obtain position signals of the three corresponding directions of the space points; in addition, the micro light detector 12 also obtains light intensity signals of the corresponding space points and transmits the light intensity signals to the control device; the control means 13 thus obtains a set of light intensity signals and position signals.

The result of the three-dimensional grid-type volume scan measurement of one microchannel is the optical information of the three-dimensional volume lattice, and the three-dimensional volume is about 40 × 40 μm. The working limit frequency of three-dimensional scanning is more than 1kHz

The rest of fig. 1 except the control device 13 can be referred to as a miniature three-dimensional self-scanning confocal microscope detector. It can form an array of miniature three-dimensional self-scanning confocal microscope detectors to improve the working efficiency.

The dot type light source 1 employs a dot type semiconductor laser of power μ W class, whose light emitting area is less than 5 μm in size. The micro-optical beam splitter 3 is made of polysilicon, and the mirror of the micro-scanning reflector 4 is made of polysilicon and an aluminum film; the micro lens is made of polymer, and has a focal length less than 1.0mm and a diameter less than 0.5 mm.

The micro scanning reflector 4 and the double comb-shaped linear scanner in the micro three-dimensional self-scanner are driven by electrostatic effect (or electromagnetic effect).

The pinholes 10 are made in a gold film with a pore size of less than 5 μm.

The present invention is not limited to the above-described examples, and those skilled in the art can implement the present invention in various embodiments based on the present disclosure.

Claims

1. A miniature three-dimensional self-scanning confocal microscope is characterized in that: the micro-scanning micro-lens system comprises a point type light source (1), a first micro-lens (2), a micro-optical beam splitter (3), a micro-scanning reflector (4), a second micro-lens (5), a double comb-shaped linear scanner, a third micro-lens (10), a pinhole (11), a micro-optical detector (12) and a control device (13); wherein,

the double-comb linear scanner is composed of a rotor (6), two X-direction linear drivers (7) and a Z-direction linear driver (8), wherein the X-direction linear drivers (7) and the Z-direction linear drivers (8) are used as stators, the second micro lens (5) is positioned on the rotor (6), the X-direction linear drivers (7) are used for driving the rotor (6) to move along the X direction, and the Z-direction linear drivers (8) are used for driving the rotor (6) to move along the Z direction;

light emitted by the point light source (1) passes through the first micro lens (2) and becomes collimated laser beams; the collimated laser beam penetrates through the micro optical beam splitter (3), is reflected by the micro scanning reflector (4), and is focused on a sample (9) by the second micro lens (5); reflected light or fluorescence is reflected by a second micro lens (5) and a micro scanning reflector (4) along an original light path in sequence and then returns to the micro optical beam splitter (3), and the light reflected by the micro optical beam splitter (3) irradiates a micro optical detector (12) through a third micro lens (10) and a pinhole (11) and is converted into a photoelectric signal to be transmitted to a control device (13);

the control device (13) controls the micro-scanning mirror (4) to deflect and scan, and focal point scanning in the Y direction is formed on the focal plane of the second micro lens; the control device (13) controls the X-direction linear driver (7) to drive the rotor (6) clamping the micro lens (5) to form X-direction focus linear scanning; a control device (13) controls a Z-direction linear driver (8) to drive a mover (6) clamping the micro lens (5) to form a Z-direction focal point linear scan; the control device (13) acquires and processes the three-dimensional scanning signals to obtain position signals of the three corresponding directions of the space points; the micro light detector (12) obtains light intensity signals of the corresponding space points and transmits the light intensity signals to the control device, and the control device (13) obtains a set of the light intensity signals and corresponding position signals.