WO2005026812A1

WO2005026812A1 - Optics channel

Info

Publication number: WO2005026812A1
Application number: PCT/KR2004/002356
Authority: WO
Inventors: Eui Chang Chung; Jung Young Lee; Nam Jin Yoo; Won Sang Park; Sug Hyung Lee
Original assignee: Jung Woo International Co., Ltd
Priority date: 2003-09-16
Filing date: 2004-09-16
Publication date: 2005-03-24
Also published as: KR20050027608A

Abstract

The present invention provides an optical channel in which an optical definition of a sample is significantly improved and a difference between a focus of a laser beam and a focus of a microscope view is compensated for simply when micro analysis and/or micro-work for microdissection, etc. are performed. The optical channel comprises a first optical channel that forms a first optical axis of a microscope device, a second optical channel that forms a second optical axis of a laser beam generated from a laser device, a dichroic mirror that passes the first optical axis and refracts the second optical axis toward an objective lens of the microscope device, and a correction unit disposed between the dichroic mirror and a monitoring unit of the microscope device.

Description

TITLE OPTICS CHANNEL

TECHNICAL FIELD The present invention relates to a common optical channel for use in a microdissection system that cuts a tissue slice, etc., which is monitored by an optical microscope using a laser beam.

BACKGROUND ART For example, microdissection technology is adapted to extract a predetermined portion of a cell, etc. which is monitored by an optical microscope for the purpose of genetic variation of DNA, RNA or protein at a specific cell or a portion of a biological tissue, subsequent research, etc. In carrying out microdissection technology, it is required that a tissue sample be optically monitored exactly, regions to be sliced be selected finely and a selected sample be dissected accurately using a laser. It is, however, difficult to obtain accurate microdissection and dissected slices of the tissue using the laser even through a common microscope. A microdissection system has been developed in order to solve this problem. Microdissection systems disclosed in U.S. Patent Application No.

09/043,093, PCT Publication Nos. WO99/39176 and WO00/34757, U.S. Patent No.6, 010,888 and the like are adapted to monitor and dissect a sample using a slide. Microdissection is performed with optical definition of the sample being very low. Therefore, lesion, etc. having minute variation such as precancerous lesion cannot be identified sufficiently with a microscope view. Meanwhile, an attempt for increasing the optical definition has been made by providing a precision objective lens in an optical channel. However, this method leads to increased cost of the objective lens and has a limited definition. In a system for micro-analysis and/or micro-work, a focus for monitoring and a focus for a work are frequently different. It is thus very important to compensate for the difference between the focuses. More particularly, if the spot size and the focus of the laser beam are controlled depending on variation in the objective lens and the state of samples, such correction in the focus becomes more important. However, the optical channel for the conventional micro-analysis and/or micro-work system does not have this correction device.

DISCLOSURE OF THE INVENTION Accordingly, the present invention has been made in view of the above problems, and the present invention is adapted to provide an optical channel in which an optical definition of a sample is significantly improved and a difference between the focus of a laser beam and the focus of a microscope view is compensated in a simple manner when micro-analysis and/or micro-work for microdissection, etc. are performed. To achieve the above object, according to the present invention, there is provided an optical channel, comprising a first optical channel that forms a first optical axis of a microscope device, a second optical channel that forms a second optical axis of a laser beam generated from a laser device, a dichroic mirror that passes the first optical axis and refracts the second optical axis toward an objective lens of the microscope device, and a correction unit disposed between the dichroic mirror and a monitoring unit of the microscope device. The correction unit comprises a concave lens that is aligned along the first optical axis corresponding to the objective lens of the microscope device, and a plurality of correction lens for correcting a characteristic of the objective lens, which are aligned along the first optical axis. The second optical channel comprises a prism for refracting the laser beam generated from the laser device, and a plurality of collimators for making a reflecting laser beam of the prism incident upon the dischroic mirror as a parallel beam.

BRIEF DESCRIPTION OF THE DRAWINGS Further objects and advantages of the invention can be more fully understood from the following detailed description taken in conjunction with the accompanying drawings in which: FIG. 1 is a conceptual view of an optical channel according to the present invention; FIG. 2 is a cross-section view showing a channel box for a second optical channel having a correction unit; FIG. 3 is a plan view of the channel box shown in FIG. 2; FIG. 4 is an expanded plan view of the correction unit; and FIG. 5 is a cross-section view showing the correction unit taken along lines A-A in FIG. 4.

BEST MODE FOR CARRYING OUT THE INVENTION An optical channel for a microdissection system will now be described in detail in connection with preferred embodiments of the present invention with reference to the accompanying drawings. In FIG. 1 , an optical channel 100 according to the present invention includes a first optical channel 10 and a second optical channel 20. The first optical channel 10 forms a first optical axis 12 of a microscope device and the second optical channel 20 forms a second optical axis 24 of a laser beam generated from a laser device 22. The first optical channel 10 is adapted to monitor a sample on a slide 40 using an eyepiece 32 or a CCD camera 34 of a monitoring unit 30. The first optical channel 10 is an assembly of an eyepiece prism 14, a tube lens 16, an objective lens 18, a condenser 11 and a lamp 13. In this time, the first optical axis 12 refers to an image-monitoring path. The second optical channel 20 is a path along which the laser beam for selecting a work such as dissection against a predetermined region of a sample moves. The path is displayed as the second optical axis 24. The second optical channel 20 has a prism 26, a pair of collimators 28, 21 , and a shutter 23. Referring to FIGS. 2 and 3, it is preferred that the second optical channel 20 is located in a channel box 25 that is substantially sealed so that a predetermined optical axis can be formed stably although the intensity of the laser beam is changed, if needed. The laser device 22 is designed to have a spot size of below 1 μm . The power of the laser beam generated from the laser device 22 can be controlled by a user. The laser device 22 includes a solid-state laser having a wavelength of 355nm, a spectrum of 20uJ and a frequency of 50 to 10000Hz. A beam inlet 27 upon which the laser beam generated from the laser device 22 (see FIG. 1) is incident is formed at one end of the channel box 25. First and second ports 29a, 29b in which the first optical axis 12 is formed are formed at the other end of the channel box 25. The first port 29a is connected to the monitoring unit 30 and the second port 29b is connected to the objective lens 18. The prism 26 is disposed within the channel box 25, and it serves to refract a laser beam such as an ultraviolet laser, which is generated from the laser device 22, toward the collimators 21, 28. Further, the prism 26 make the laser beam through the prism 26 parallel, so that it helps a spot size necessary for the microdissection system to be obtained. If the collimators 21 , 28 are erroneously arranged, not only a parallel laser beam cannot be obtained, but also an exact focus cannot be obtained or a focus can be inaccurate although the focus is brought. In this time, the collimator can be classified into a concave lens type eyepiece collimator 28 and an object type collimator 21 which looks like a convex lens. Each of the collimators 21 , 28 is disposed at one end of a body tube having a predetermined length. The object type collimator 21 is located adjacent to a concave lens 21a which is disposed to face the shutter 23, and a convex lens 21b located to face a dichroic mirror 50. If the concave lens 21a and the convex lens 21b are arranged, the object type collimator 21 has the properties of the convex lens. The shutter 23 is located between the eyepiece type collimator 28 and the object type collimator 21. It is preferred that the shutter 23 is opened when micro- work is performed and is shut when other works are performed. The dichroic mirror 50 is disposed in the first optical axis 10 around a portion where the second optical axis 20 is refracted. The dichroic mirror 50 serves to pass the first optical axis 10 in a straight line and to refract the second optical axis 20. That is, the dichroic mirror 50 transmits an image of a sample, which is monitored through the objective lens 18 of the microscope device, toward the monitoring unit 30, and it reflects the laser beam incident upon the laser device 22 toward the objective lens 18. The dichroic mirror 50 has the property in which light of a given wavelength is reflected and light of other wavelengths is transmitted due to an interference effect of light within a thin film when an incident angle of light is 45° in a flat mirror on which a transparent multilayer thin film is coated. The dichroic mirror 50 can have a plate shape and a prism shape. In this embodiment, the dichroic mirror 50 has the plate shape. A thickness or the number of layers of the film can be different, if appropriate, and some of a visible ray can be selected freely depending on a material. Referring again to FIGS. 1 and 2, a correction unit 60 having a characteristic of a concave lens is located between the dichroic mirror 50 and the monitoring unit 30. A filter 70 is located between the correction unit 60 and the dichroic mirror 50. The correction unit 60 can increase the definition of the microdissection system, for example, when a sample is monitored and dissected, by complementing the characteristic of the objective lens 18. The correction unit 60 serves to correct a difference between the focus of a sample which is recognized through the CCD camera 34 or the eyepiece 32 and the focus when a predetermined region of the sample is dissected using a laser beam. The correction unit 60 can make a spot size of the laser beam of the microdissection system constant regardless of variation in the power of the laser beam. More particularly, even when the power of the laser beam is raised in order to accelerate micro-work, the spot size of the laser beam can be kept constant by means of the correction unit 60. The correction unit 60 includes a correction lens 62 capable of correcting the definition irrespective of characteristics such as magnification of the objective lens 18 of the microscope device. The correction lens 62 is aligned in the first optical axis 10. A portion of the correction lens 62 that faces the dichroic mirror 50 has a flat shape, and a portion of the correction lens 62 that faces the monitoring unit 30 has a concave shape. The filter 70 intercepts a reflected light of the laser beam that passes through the dichroic mirror 50, thus preventing the monitoring unit 30, i.e., the eyepiece 32 and the CCD camera 34 from being damaged. The filter 70 can be a flat mirror, or can be formed using plastic, etc. which has good reflexibility. The filter 70 is disposed against the first optical axis 10 with slant at a given angle. The correction unit 60 has a correction tray 64 in which a plurality of correction lens 62 is disposed in a radial direction. The correction tray 64 can rotate at a given angle. The correction tray 64 is disposed in a rotary shaft 66 which can rotate against the channel box 25. A follower gear 64a is formed on the outer circumference of the correction tray 64. The follower gear 64a is engaged with a driving gear 68a formed in the rotary shaft of a motor 68. The motor 68 is controlled by a control unit (not shown) and can rotate in a forward or reverse direction. FIG. 4 illustrates six correction lens 62 which are disposed in the correction tray 64 one by one at places where the circumference is divided among the six. In this case, if magnification changes depending on variation in the objective lens, the correction lens 62 corresponding to the objective lens can be located in the first optical axis 10 as the correction tray 64 is rotated by the motor 68. As such, the correction lens 62 can correct a difference in the focus with the objective lens 18 when the system operates.

INDUSTRIAL APPLICABILITY As described above, according to the present invention, a correction unit having a correction lens of a concave lens shape can simply correct a difference in the focus depending on a characteristic of an objective lens. Accurate micro-work is thus possible because an optical definition of various systems developed for micro-analysis and/or micro-work, which employ an optical channel, is improved. Further, a difference between the focus of a laser beam and the focus needed when a sample is monitored in a system requiring an accurate work such as dissection of a sample can be corrected in simple and exact manners. Accordingly, a fine and exact work can be performed while keeping a spot size of a laser beam constant. Further, the optical channel of the present invention can be applied to a field of an optical system such as a microscope.

Claims

WHAT IS CLAIMED IS:

1. An optical channel, comprising: a first optical channel for forming a first optical axis of a microscope device; a second optical channel for forming a second optical axis of a laser beam generated from a laser device; a dichroic mirror for passing the first optical axis and refracting the second optical axis toward an objective lens of the microscope device; and a correction unit disposed between the dichroic mirror and a monitoring unit of the microscope device.

2. The optical channel as claimed in claim 1 , wherein the correction unit comprises a concave lens that is aligned along the first optical axis corresponding to the objective lens of the microscope device, and a plurality of correction lens for correcting a characteristic of the objective lens, which are aligned along the first optical axis.

3. The optical channel as claimed in claim 1 , wherein the second optical channel comprises a prism for refracting the laser beam generated from the laser device, and a plurality of collimators for making a reflecting laser beam of the prism incident upon the dischroic mirror as a parallel beam.