JP2009116082A - Optical scanning unit and observation apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical scanning unit which can be made in a small size and an observation apparatus in which an optical system is easily replaced. <P>SOLUTION: The optical scanning unit 50 includes an MEMS optical scanner which repeatedly tilts a mirror M and an objective lens 52, and light is scanned with the mirror which is tilted by the MEMS optical scanner and emitted along an optical axis of the objective lens via the objective lens. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical scanning unit that scans and emits light and an observation apparatus using the optical scanning unit.

  Conventionally, when a scanning optical system is attached to an observation microscope that magnifies and observes an observation target, in order to irradiate the observation target with the scanning light, an optical system including a mirror or the like is externally attached.

  However, if a conventional optical scanning optical system using a polygon mirror, a galvanometer mirror and a lens optical system is used as the above-described scanning optical system, it becomes unsuitable because it becomes large as an external device. In addition, the optical system cannot be used for general purpose.

  An object of the present invention is to provide an optical scanning unit that can be reduced in size and an observation device that allows easy replacement of an optical system in view of the above-described problems of the prior art.

  In order to achieve the above object, the optical scanning unit according to the present embodiment includes a MEMS optical scanner that repeatedly tilts a mirror and an objective lens, and scans the light with a mirror that is tilted by the MEMS optical scanner and scans the objective. The light is emitted along the optical axis of the objective lens through the lens.

  According to this optical scanning unit, scanning light can be obtained by repeatedly tilting a mirror with a MEMS optical scanner and scanning the light, and emitted along the optical axis of the objective lens via the objective lens. it can. MEMS (abbreviation) is an abbreviation for micro electro mechanical systems, and is a small device in which mechanical component parts are manufactured in a minimum size. The MEMS optical scanner is a MEMS optical device that scans light by driving a mirror by an actuator, and is configured to be small in size and highly reliable and stable in operation. Thus, by using the MEMS optical scanner for optical scanning, it is possible to realize an optical scanning unit that can be miniaturized and operates stably.

  The optical scanning unit irradiates the observation object with the scanning light through the objective lens, and emits light incident on the objective lens from the observation object through an optical system to observe the observation object. Can be configured for an observation device.

  In this case, the light scanning unit configured to be small is observed by configuring the light incident on the objective lens from the observation object to be emitted along the optical axis of the objective lens through the optical system. Can be exchanged for the device.

  The observation apparatus of the present embodiment includes the above-described optical scanning unit. Accordingly, the optical system can be easily replaced by using the above-described small optical scanning unit in an observation apparatus such as a microscope.

  According to the optical scanning unit and the observation apparatus of the present invention, the size can be reduced, and the optical system can be easily replaced.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of the entire optical scanning unit according to the present embodiment.

  As shown in FIG. 1, the optical scanning unit 50 includes a mirror M, a collimating lens 51, an objective lens 52, total reflection mirrors 53, 54, and 55, and a half mirror 56 in a housing 50a. . The mirror M constitutes a part of the MEMS optical scanner. The objective lens 52 is composed of, for example, an aspheric lens or an Fθ lens.

  Light from a light source 57 composed of a semiconductor laser or the like is introduced into the collimating lens 51 of the optical scanning unit 50 through the optical fiber FI. The light collimated by the collimating lens 51 enters the mirror M, is reflected by the mirror M, passes through the half mirror 56, passes from the objective lens 52 to the outside of the optical scanning unit 50, and the optical axis of the objective lens 52 in the direction k. It emits along a.

  Further, the light incident from the outside of the optical scanning unit 50 passes through the objective lens 52 and is reflected by the half mirror 56, and subsequently reflected by the mirrors 55, 54, and 53 and then outward of the optical scanning unit 50 in the direction m. The light is emitted along the optical axis a of the objective lens 52.

  The mirror M in FIG. 1 constitutes a part of the MEMS optical scanner. The MEMS optical scanner will be described with reference to FIGS. 2 and 3.

  FIG. 2 is a schematic diagram for explaining the basic structure and operating principle of a MEMS optical scanner that can be used in the optical scanning unit of FIG. FIG. 3 is a top view (a) showing a specific example of a MEMS optical scanner that can be used in the optical scanning unit of FIGS. 1 to 3, a cross-sectional view (b), and a bottom view (c) taken along line bb. is there.

  In the MEMS optical scanner shown in FIG. 2, a rectangular planar mirror M is formed in a rectangular yoke Y so as to be connected to the yoke Y by a pair of torsion bars T, T, and a drive coil is formed along the outer periphery of the mirror M. D is formed, and a pair of permanent magnets P1 and P2 is disposed so as to face the outside of the yoke Y, and is an electromagnetically driven resonance type in which a mirror is driven by an electromagnetically driven actuator.

  In the MEMS optical scanner, as shown in FIG. 2, when a magnetic field having a magnetic flux density B is generated in a direction perpendicular to the torsion bars T and T by the permanent magnets P1 and P2 and a current i is supplied to the drive coil D, rotation by Lorentz force F occurs. The torsion bars T and T are rotated against the elastic restoring force by torque, and the mirror M is tilted. By making the current i an alternating current, the torsion bars T and T resonate and rotate in the rotation direction r and the opposite direction r ′, so that the mirror M resonates and repeats the inclination. Since F∝i · B, the inclination of the mirror M can be changed by changing the amount of current. Since the mirror M is inclined in the rotation directions r and r 'and changes the direction of light incident on the mirror M and reflected in one direction, the MEMS optical scanner in FIG. 2 is a one-dimensional movable type.

  Specifically, as shown in FIGS. 3A to 3C, the MEMS optical scanner 1 is provided with a yoke 4 on the reference surface 6 a side of the substrate 6, and with the permanent magnets 2 and 3 facing the inside of the yoke 4. The silicon chip 7 is provided between the permanent magnets 2 and 3, the mirror 5 is disposed so as to be surrounded by the silicon chip 7, a drive coil is formed as shown in FIG. 3b, the mirror 5 resonates in the rotation direction r around the rotation center axis p and in the opposite direction r ′ as shown in FIGS. This is repeated, and is configured as a one-dimensional movable type electromagnetically driven resonance type.

  In the MEMS optical scanner 1 shown in FIGS. 3A to 3C, when the incident light n is reflected by the mirror M on the opposite surface 6b side of the reference surface 6a of the substrate 6, the reflected light n ′ is reflected on the reference surface 6a. The angle changes according to the tilt angle of the mirror 5. The MEMS optical scanner 1 is provided with a torsion bar similar to the torsion bar T in FIG. 2 on the rotation center axis p.

  The MEMS optical scanner 1 shown in FIGS. 3A to 3C is configured so that each component is very small, and the overall dimensions thereof are, for example, 30 mm × 22 mm × 5 mm (thickness). Is 4 mm × 4 mm. Such a MEMS optical scanner is sold, for example, by Nippon Signal Co., Ltd. under the trade name “ECO SCAN: ESS115B”.

  The MEMS optical scanner 1 is disposed at the position of the mirror M in FIG. That is, the MEMS optical scanner 1 has mounting holes 6c at the four corners of the substrate 6, and the mirror 5 is a function of the mirror M at a predetermined position in the housing 50a of the optical scanning unit 50 in FIG. It attaches with the attachment hole 6c so that it may exhibit.

  Next, optical scanning in the optical scanning unit 50 of FIGS. 1 to 3 will be described. The light from the light source 57 is collimated by the collimating lens 51 and enters the mirror M. The mirror M corresponds to the mirror 5 of the MEMS optical scanner 1 in FIGS. 3A to 3C, and an alternating current is passed through the MEMS optical scanner 1 like the drive coil D in FIG. It vibrates by repeating the rotation around the rod T and repeating the inclination.

  Due to the vibration of the mirror M of the MEMS optical scanner 1 as described above, the reflected light when the light from the light source 57 is reflected by the mirror M is scanned in the horizontal direction H in the figure with respect to the optical axis a in FIG. The light is emitted from the optical scanning unit 50 as scanning light.

  The optical scanning unit 50 shown in FIGS. 1 to 3 can be applied to an objective lens unit of an observation apparatus such as a microscope. That is, the scanning light obtained by scanning the surface A1 of the observation object A on the table D provided on the lower side of the optical scanning unit 50 in FIG. By scanning, the light reflected by the surface A1 is emitted in the direction m through the optical scanning unit 50 while irradiating the surface A1 of the observation object A with the scanning light. The reflected light from the surface A1 enters the eyepiece or the like provided on the upper side of the optical scanning unit 50, whereby the surface A1 of the observation object A can be observed.

  As described above, the MEMS optical scanner is a MEMS optical device that scans light by resonating a mirror by an electromagnetically driven actuator, and is configured in a small size and has high reliability and stable operation. By using the scanner for optical scanning of the optical scanning unit 50, the apparatus can be miniaturized and operates stably.

  According to a conventional optical scanning optical system using a polygon mirror or a galvanometer mirror and a lens optical system, the overall configuration of the apparatus is large and expensive. By using the optical scanner, an inexpensive and downsized optical scanning unit can be realized, and power consumption can be reduced as compared with the conventional configuration.

  Since the optical scanning unit 50 of FIG. 1 can be configured in a small size, as described above, it can be applied to the objective lens unit of an observation apparatus such as a microscope, and can observe an observation object while irradiating scanning light. By preparing and replacing a plurality of optical scanning units in which the magnification of the lens 52 is changed, it is possible to easily observe the optical system by changing the magnification by changing the optical system.

  For example, the housing 50a containing the optical system as shown in FIG. 1 is configured in the size of the objective lens portion of a commercially available microscope, and the scanning light can be easily obtained simply by attaching the optical scanning unit 50 to the objective lens revolver of the commercially available microscope. Can be configured to illuminate. As a result, it is possible to observe the scanning light while illuminating it, and the optical system can be easily replaced simply by rotating the revolver. Thereby, it becomes possible to attach the optical scanning unit and use the existing microscope as it is.

  As described above, the best mode for carrying out the present invention has been described. However, the present invention is not limited to these, and various modifications are possible within the scope of the technical idea of the present invention. For example, the scanning length of the scanning light on the surface A1 of the object A can be adjusted within a predetermined range by changing the mirror tilt angle by changing the drive current amount of the mirror M to the MEMS optical scanner 1. .

  1 to 3 is a one-dimensional movable type that tilts the mirror M in one direction. However, the present invention is not limited to this, and the two-dimensional movable that tilts the mirror M in two directions. It is good also as a type. That is, the two-dimensional movable type MEMS optical scanner configured by adding the permanent magnet, the torsion bar, the drive coil, etc. of FIG. 4 is used in FIG. it can. Specifically, such a two-dimensional movable type MEMS optical scanner has an overall size of, for example, 50 mm × 35 mm × 9 mm (thickness), and a mirror plane size of 4 mm × 3 mm. It is sold as a product name "ECO SCAN: ESS212B" by the corporation. Further, in order to obtain scanning light that is two-dimensionally scanned, two one-dimensional movable type MEMS optical scanners as shown in FIGS. 2 and 3 may be used.

  Moreover, although the MEMS optical scanner was comprised from the resonance type displaced by an alternating current, the MEMS optical scanner displaced by a direct current may be sufficient.

  Further, the light source 57 of the optical scanning unit 50 may be provided in the housing 50a of FIG. 1, and in this case, the optical fiber FI can be omitted.

  Further, the optical scanning unit 50 in FIG. 1 can be applied not only to a normal optical microscope but also to a phase contrast microscope system and a fluorescence microscope system. In addition to a microscope, for example, an exposure apparatus, a shape measuring unit, It can also be applied to a fluorescence measurement unit.

It is a figure which shows the schematic structure of the whole optical scanning unit by this Embodiment. FIG. 2 is a schematic diagram for explaining a basic structure and an operation principle of a MEMS optical scanner that can be used in the optical scanning unit of FIG. 1. FIG. 4 is a top view (a) showing a specific example of a MEMS optical scanner that can be used in the optical scanning unit of FIG. 1, a cross-sectional view (b), and a bottom view (c) taken along line bb.

Explanation of symbols

DESCRIPTION OF SYMBOLS 50 Optical scanning unit 50a Case 51 Collimating lens 52 Objective lens 53-55 Total reflection mirror 56 Half mirror 57 Light source A Observation target A1 Surface FI Optical fiber H Horizontal direction M Mirror a Optical axis of objective lens k Scanning light emission direction m Reflected light from the observation object

Claims (4)

  An optical scanning device comprising: a MEMS optical scanner that repeatedly tilts a mirror; and an objective lens, wherein light is scanned by the mirror tilted by the MEMS optical scanner and emitted along the optical axis of the objective lens through the objective lens. unit.   Claims for an observation apparatus for observing the observation object by irradiating the observation object with the scanning light through the objective lens and emitting light incident on the objective lens from the observation object through an optical system. Item 4. The optical scanning unit according to Item 1.   The light scanning unit according to claim 2, wherein light incident on the objective lens from the observation object is emitted along the optical axis of the objective lens through the optical system.   An observation apparatus comprising the optical scanning unit according to any one of claims 1 to 3.

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