1、This is a application of Application Ser. No. 10/799,595, filed on Mar. 15, 2004 now U.S. Pat. No. 7,081,700. FIELD OF THE INVENTION The present invention relates to a manipulator such as a minute component assembly apparatus which assembles a minute object such as a micromachine component or unit b
2、y using a magnifying observation device such as an optical microscope, electron microscope, or scanning tunneling microscope, or a compact manipulator apparatus which performs diagnosis, medical treatment, research, biological production, or the like by physically manipulating, for example, minute t
3、issues, cells, or genes of a living body and a minute object manipulating apparatus using the manipulator. BACKGROUND OF THE INVENTION There have been known a technique of controlling the posture of a manipulating member (end-effector) by rotating a general size arm using a general size bearing and
4、a technique of performing a necessary process on a minute work in a working device by rotating an arm or tool along an arcuated guide (see, for example, Japanese Patent Laid-Open No. 7-256575). In a conventional apparatus like those described above, if the distal end of an end-effector is not locate
5、d on the rotation axis of a bearing or arcuated guide, the distal end of the end-effector moves out of the visual field or depth of focus of a microscope due to posture control operation. This makes it necessary to position the microscope and the distal end of the end-effector again. As described ab
6、ove, in a manipulator which manipulates a minute object, when the posture of the end-effector at the distal end is controlled, the manipulation target object often moves out of the visual field of the microscope. In a conventional manipulator having three degrees of rotational freedom, in particular
7、, since the rotation axes corresponding to the respective degrees of freedom do not coincide with each other and do not cross at one point, the distal end of the end-effector tends to move out of the visual field or depth of focus of the microscope due to posture control operation. In such a case, t
8、he microscope and the distal end of the end-effector must be positioned again. This operation requires a long period of time. SUMMARY OF THE INVENTION It is an object of the present invention to provide a manipulator such as a compact manipulator apparatus which solves the above problems and manipul
9、ates a minute target object, and a minute object manipulating apparatus or the like using the manipulator. In order to achieve the above object, according to the present invention, there is provided a manipulator comprising: a manipulation target object manipulating member being driven and controlle
10、d by a plurality of free rotation axes； all the plurality of free rotation axes crossing at one point； and, a manipulation distal end portion of the manipulating member being placed near the intersection. According to this arrangement, the manipulator has a mechanism in which a plurality of (typical
11、ly three) free rotation axes cross at one point, and the distal end portion of a manipulating member (end-effector) which manipulates a manipulation target object is placed near the intersection. With this structure, even if, for example, the posture of the end-effector is changed, its distal end po
12、rtion can be made to remain within the visual field of a microscope. The following embodiment can be provided on the basis of the above basic arrangement. According to an embodiment of the present invention, the manipulating member is integrally mounted on a spherical shell movable member, the manip
13、ulation distal end portion of the manipulating member is placed near the center of the spherical shell movable member, the spherical shell movable member is in contact with a vibration member which can vibrate, and rotation of the spherical shell movable member around the center thereof is controlle
14、d by controlling vibration of the vibration member, thereby controlling a posture of the manipulating member. When the rotation of the movable member in the form of a spherical shell is controlled by controlling the vibration of the vibration member, the distal end portion of the end-effector is mad
15、e to remain within the visual field of the microscope even if the posture of the end-effector is changed. According to another embodiment of the present invention, the manipulator further comprises: first rotating means for rotating a first rotating shaft on which a first arm is mounted； second rota
16、ting means for rotating a second rotating shaft which is mounted on the first arm and on which a second arm is mounted； and third rotating means for rotating a third rotating shaft which is mounted on the second arm and on which a third arm is mounted, wherein the manipulating member is mounted on t
17、he third rotating shaft, and the first, second, and third rotating shafts pass through a manipulation distal end portion of the manipulating member. In addition, in order to achieve the above object, according to the present invention, there is provided a minute object manipulating apparatus compris
18、ing: a manipulator comprising a manipulation target object manipulating member being driven and controlled by a plurality of free rotation axes, all the plurality of free rotation axes crossing at one point, and a manipulation distal end portion of the manipulating member being placed near the inter
19、section； a magnifying observation device for magnifying observation of the manipulation target object and the manipulation distal end portion of the manipulating member； and a remote controller for remotely controlling the manipulator. This apparatus also makes the most of the advantages of the abov
20、e manipulator. In addition, for example, the manipulator can be placed on the upper side of a manipulation target object, and the magnifying observation device can be placed on the lower side of the manipulation target object. Other features and advantages of the present invention will be apparent f
21、rom the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be descr
22、ibed in detail in accordance with the accompanying drawings. First Embodiment The first embodiment of the present invention will be described first with reference to FIGS. 1 and 2A to 2D. This embodiment uses a mechanism in which all the axes corresponding to three degrees of rotational freedom cros
23、s at one point. In this system, the center of the distal end manipulating portion of an end-effector is placed near the center of the spherical rotating member of a vibration actuator having three degrees of freedom like the one disclosed in Japanese Patent Laid-Open No. 11-220891. In such a vibrati
24、on actuator, rotation axes can be arbitrarily set. Since all the rotation axes pass through the center of a spherical rotating member, a simple system with high rigidity can be formed by using this actuator. As a sensor for feeding back the position and velocity of the spherical rotating member, a t
25、wo-dimensional position sensor using a detection principle like that disclosed in Japanese Patent Laid-Open No. 10-65882 is suitably used. This sensor irradiates a spherical surface with light emitted from an irradiation source based on the optical mouse system or the like to form an irradiation pat
26、tern constituted by a high-luminance region and a relatively low-luminance region corresponding to the minute shape of the spherical surface. Movement information is then obtained by using the movement of the irradiation pattern based on the relative movement between the spherical surface and the sensor. FIG. 1 is a view which is most indicative of the main part of this embodiment. Reference numerals 20-1, 20-2, and 20-3 denote the first, second, and third elastic
