Abstract: A near-field photon tunneling device consisting of a plurality of optical waveguides, such as optical fibers, arranged in juxtaposition with a variable tunnel gap through which photons from at least one of said optical fibers can be caused to tunnel, and wherein the tunnel gap is filled with a metal that is liquid at room temperature or at moderately elevated temperature. The width of the tunnel gap and the corresponding thickness of the liquid metal layer is remotely controllable. The control mechanisms for the width of the gap include optical means, piezo-electric elements and temperature sensitive means. The devices include optical couplers of the head-on and side-on types, optical modulators and switches, as well as display units.

Abstract: This high-density optical data storage unit comprises a storage medium supported on a mechanically stable substrate, and a read/write arrangement employing a plurality of laser light sources and an interrogation light source. The laser light sources are designed as laser diodes attached to a substrate and optically aligned with an equal plurality of microlenses integrated in a first transparent layer. The read/write arrangement further comprises at least one second transparent layer, and an optional semitransparent conductive coating, said layer or said coating carrying a plurality of particulate protrusions which are also aligned with said diodes and said microlenses, said storage medium and said read/write arrangement being maintained in a mutually parallel alignment with a gap in between having a width of less than 100 nm. The protrusions in combination with the laser light sources produce dints in the medium which are representative of the data to be stored.

Abstract: This scanning near-field optical microscope is of the type where a light beam (19) with a diameter of at maximum .lambda./20 is emitted, or received, by a sharply pointed probe tip (13) which is scanned across the surface of a sample (11) to be investigated. The light reflected by, and/or transmitted through, the sample (11) is detected by a detector (16) and/or further processed by a computer (24). The distance between the light-emitting probe tip (13) and the sample (11) under investigation is on the order of .lambda./20 as well, so that the surface of the sample (11) is within the near-field of said probe tip (13). This optical microscope is characterized in that the gap between the probe tip (13) and the sample (11) is filled with a liquid (40) of high opacity, including any liquids with a large negative dielectric constant .epsilon., so as to attenuate the intensity of the lightwaves emitted or received by the probe tip (13) to such an extent that the penetration depth z.sub.

Abstract: This high-density optical data storage unit comprises a storage medium supported on a mechanically stable substrate, and a read/write arrangement employing a plurality of laser light sources and an interrogation light source. The laser light sources are designed as laser diodes attached to a substrate and optically aligned with an equal plurality of microlenses integrated in a first transparent layer. The read/write arrangement further comprises at least one second transparent layer, and an optional semitransparent conductive coating, said layer or said coating carrying a plurality of particulate protrusions which are also aligned with said diodes and said microlenses, said storage medium and said read/write arrangement being maintained in a mutually parallel alignment with a gap in between having a width of less than 100 nm. The protrusions in combination with the laser light sources produce dints in the medium which are representative of the data to be stored.

Abstract: A distance-controlled tunneling transducer comprises a plurality of tunnel tips arranged in an array at a tunneling distance from an electrically conductive surface of a storage medium. Each tip is attached to a respective cantilever beam permitting the distance between each tip and the surface to be individually pre-adjusted electrostatically. Arranged in juxtaposition with each cantilever beam is an active control circuit for adjusting the tip-to-surface distance during operation of the storage unit, thus preventing crashes of the associated tip into possible asperities on the surface of the recording medium. Each control circuit is designed such that its operating voltage concurrently serves to pre-adjust its associated cantilever beam and to maintain the tip-to-surface distance essentially constant.

Abstract: A distance-controlled tunneling transducer comprises a plurality of tunnel tips arranged in an array at a tunneling distance from an electrically conductive surface of a storage medium. Each tip is attached to a respective cantilever beam permitting the distance between each tip and the surface to be individually pre-adjusted electrostatically. Arranged in juxtaposition with each cantilever beam is an active control circuit for adjusting the tip-to-surface distance during operation of the storage unit, thus preventing crashes of the associated tip into possible asperities on the surface of the recording medium. Each control circuit is designed such that its operating voltage concurrently serves to pre-adjust its associated cantilever beam and to maintain the tip-to-surface distance essentially constant.

Abstract: In an apparatus for sensing a distance between a sensor and a surface of a body being measured, a sensor body of the sensor is formed as a light waveguide for laser light. A light exit site for light diffracted within the sensor body is located at a surface thereof which faces away from the measured body. A detection particle is located at the surface of the sensor body, which faces the measured body. The detection particle has a substantially convex and rounded off form and a major dimension which is smaller than the wavelength of the light. The measured body is located in the optical near field of the detection particle. A detector device converts the optical energy of the diffracted light into an electrical detector signal. A continuous thin film is provided as a coating on the sensor. It substantially covers the detection particle and at least a part of the surface of the sensor body in the vicinity of the detection particle.

Abstract: In a scanning tunneling microscope, the tunnel tip comprises an optically transparent body coated with a semiconductor layer, such as a GaAs layer. A sample being investigated comprises a magnetic material. Tunnel microscope operation permits investigation of the magnetic properties at or near the surface of the sample where a spin-polarized beam of light impinges upon the sample surface, through the transparent body of the tunnel tip, or after traveling through the sample, or when made to impinge upon the surface at an angle of incidence from an axis normal to the sample surface. In addition to conventional scanning tunneling microscope electronics, an oscillator-controlled phase-sensitive detector or gating means and a display unit are provided for direct viewing of the magnetic properties and the topography of the sample.

Abstract: For observing material structures and/or dynamic processes at surfaces, the known scanning tunneling microscope (STM) is combined with a photoexcitation process leading to photon-assisted tunneling. Thereby, the very fine spatial resolution of the STM is combined with the picosecond or even femtosecond time resolution of laser pulses. The tunnel tip of a scanning tunneling microscope is positioned at tunnel distance with respect to the surface of the sample to be investigated, with an appropriate potential applied across the gap between the tunnel tip and the sample. The tunneling current is gated by means of at least one pulsed laser beam directed at the tuneling region and/or at the tunnel tip.

Abstract: The method involves the steps of moving the magnetic head (8) to within aerodynamic distance from the electrically conductive surface (16) of rotating magnetic recording disk, further positioning of the head (8) until a tunnel current occurs across the gap between the head (8) and surface (16), and maintaining said tunnel current constant by using the deviations of the current from a predetermined value corresponding to a certain flying height.The apparatus comprises a tunnel electrode (9) forming an integral part of the head assembly which is attached to a distance control mechanism (5) permitting the positioning of the head assembly with a one-nanometer accuracy. The tunnel electrode (9) has a very slightly beveled shoulder (45, 47) ensuring early detection of asperities approaching the head. Gradation of the potential between tunnel electrode (9) and surface (16) of the recording disk (3) is used to enhance the response to asperities.

Abstract: This atomic force microscope includes a pointed tip (1) mounted on top of an oscillating crystal (2) which is translatable in xyz-directions by a conventional xyz-drive (4). A potential applied to a pair of electrodes (5, 6) coated on opposite faces of the crystal (2) causes the latter to oscillate with its resonance frequency. As the tip (1) is approached to a surface to be investigated, the frequency of oscillation of the crystal deviates from its original frequency. This deviation can be used in a feedback loop to control the distance in z-direction of the tip (1) from the surface being investigated and to plot an image of the contour of each scan performed by the tip (1) across the surface.

Abstract: The storage unit comprises an array of tunnel tips (13) arranged at tunneling distance from a recording surface (2a) of a storage medium (2) which is capable of permitting digital information to be written or read through variations of the tunneling current. The storage medium (2) is attached to the free end of a piezoceramic bendable tube (3). In operation, the free end of the tube (3) is moved in a circular orbit by repetitive sequential energization of oppositely arranged pairs of 90.degree. phase shifted electrodes (4,6 and 5,7). This tube movement causes each tunnel tip (13) to scan a respective unique associated annular area of the storage medium (2). To address a particular concentric track in a particular annular area, tunneling current is applied to the associated tip (13) via respective electrodes (16,18) while, concurrently, a potential is applied via electrodes (4,6 and 5,7) to tube (3) of a magnitude corresponding to the desired orbital diameter for the tube.

Abstract: The micromechanical sensor head is designed to measure forces down to 10.sup.-13 N. It comprises a common base from which a cantilever beam and a beam member extend in parallel. The cantilever beam carries a sharply pointed tip of a hard material, dielectric or not, for interaction with the surface of a sample to be investigated. Bulges forming a tunneling junction protrude from facing surfaces of said beams, the gap between said bulges being adjustable by means of electrostatic forces generated by a potential (V.sub.d) applied to a pair of electrodes respectively coated onto parallel surface of said beams. The sensor head consists of one single piece of semiconductor material, such as silicon or gallium arsenide (or any other compounds thereof) which is fabricated to the dimensions required for the application by means of conventional semiconductor chip manufacturing techniques.

Abstract: The waveguide comprises a transparent body having a very sharp point at one end and being coated with a first opaque layer, such as metal. The first opaque layer carries a layer of an optically transparent material which is covered, in turn, by a second opaque layer. The apex of the point has been removed so as to expose the transparent body through a first aperture and to expose the transparent layer through a second aperture, the first aperture occupying an area of less than 0.01 .mu.m.sup.2.Light enters the transparent body at its remote end and exits through the first aperture to illuminate an object. Reflected light from the object enters the transparent layer through the second aperture and is guided to a light detector for further processing.

Abstract: This light waveguide consists of an optically transparent body cut at one end to a sharp tip and polished optically flat at the other end. A metallization layer on its surface is thick enough to be opaque. By pressing the waveguide against a rigid plate the metallization is plastically deformed so as to expose a tiny aperture at the tip of the body through which light can pass. By carefully controlling the deformation of the metallization the diameter of the aperture can be kept between 10 and 500 nm. The waveguide can be incorporated in a semiconductor laser of a read/write head used in an optical storage device.

Abstract: An improved scanning tunneling microscope comprising a semiconductor chip into which slots are etched to form a central portion linked by a first pair of stripes to an intermediate portion, which in turn is linked by a second pair of stripes to the main body of the chip. The pairs of stripes have mutually orthogonal directions to allow the center portion to perform movements in the x- and y-directions under the control of electrostatic forces created between the stripes and their opposite walls. The center portion has formed into it at least one tongue carrying an integrated, protruding tunnel tip which is capable of being moved in the z-direction by means of electrostatic forces between said tongue and the bottom of a cavity below the tongue.

Abstract: A vacuum transfer device includes a central processing chamber and a plurality of additional chambers radially positioned around the central chamber and in vacuum-tight connection therewith. A rotatable coulisse arrangement in the central chamber is extendable so as to reach into the additional chambers when correctly aligned. The device can transfer objects among several work stations without intermediate venting and re-evacuation of the system of chambers.

Abstract: This optical near-field scanning microscope comprises an "objective" (aperture) attached to the conventional vertical adjustment appliance and consisting of an optically transparent crystal having a metal coating with an aperture at its tip with a diameter of less than one wavelength of the light used for illuminating the object. Connected to the aperture-far end of the "objective" is a photodetector via an optical filter and an optical fiber glass cable. Scanning the object is done by appropriately moving the support along x/y-coordinates. The resolution obtainable with this microscope is about 10 times that of state-of-the-art microscopes.

Abstract: The rotator comprises a piezoelectric bender (4) pivotally supported (2, 3) at one end and carrying a means for being clamped (6) to which a "payload" (7) may be attached. The bender (4) has split electrodes to keep its ends parallel when energized. Normally engaging the means for being clamped (6) are clamping members (15, 17) attached to a pair of piezoelectric benders (10, 11) which are fixed in supports (12, 13) resting on a base plate (1).With the pair of benders (10, 11) energized, the means for being clamped (6) is released and energization of the central bender (4) results in the lifting of the payload (7) by one step. The means for being clamped (6) is then re-arrested and its pivot (2, 3) released by means of actuating the ends of bimorphs (10, 11) associated with clamping members 14 and 16 and the central bender (4) is permitted to stretch. The rotator is then prepared for the next step of rotation about the pivot (2). This embodiment permits rotation through about 15 degrees.

Abstract: A distance-controlled tunneling transducer comprises a plurality of tunnel tips arranged in an array at a tunneling distance from an electrically conductive surface of a storage medium. Each tip is attached to a respective cantilever beam permitting the distance between each tip and the surface to be individually pre-adjusted electrostatically. Arranged in juxtaposition with each cantilever beam is an active control circuit for adjusting the tip-to-surface distance during operation of the storage unit, thus preventing crashes of the associated tip into possible asperities on the surface of the recording medium. Each control circuit is designed such that its operating voltage concurrently serves to pre-adjust its associated cantilever beam and to maintain the tip-to-surface distance essentially constant.