Patent Description:
The present invention generally relates to a digital pathology scanning apparatus and more particularly relates to a carousel that supports plural physical slide racks.

Digital pathology is an image-based information environment which is enabled by computer technology that allows for the management of information generated from a physical slide. Digital pathology is enabled in part by virtual microscopy, which is the practice of scanning a specimen on a physical glass slide and creating a digital slide image that can be stored, viewed, managed, and analyzed on a computer monitor. With the capability of imaging an entire glass slide, the field of digital pathology exploded and is currently regarded as one of the most promising avenues of diagnostic medicine in order to achieve even better, faster and cheaper diagnosis, prognosis and prediction of cancer and other important diseases. <CIT> relates to a microscope slide holding cassette which includes a main body for surrounding and protecting microscopes, and shelves capable of holding the microscope slides. The shelves have support members that extend outwardly in order to support label ends of slides. Catches carried at the end of the support members are capable of limiting movement of the slides during transport of the cassette. To transport slides to different workstations, a pickup device can use a vacuum to pick up a slide without contacting areas of the slide that may have glue. The pickup device can load and unload the cassette. The pickup device can have a low-profile configuration in order to access relatively small spaces for processing flexibility. <CIT> relates to systems methods including a design of a microscope slide scanner for digital pathology applications which provides high quality images and automated batch-mode Operation at low cost. The Instrument architecture is advantageously based on a convergence of high performance, yet low cost, computing technologies, interfaces and software standards to enable high quality digital microscopy at very low cost. Also provided is a method based in pari on a stitching method that allows for dividing an image into a number of overlapping tiles and reconstituting the image with a magnification without substantial loss of accuracy. A scanner is employed in capturing snapshot images. The method allows for overlapping images captured in consecutive snapshots. <CIT> relates to a conveying device including: a storage unit storing two or more sheets of slide glasses to be subjected to a predetermined treatment; a stage holding only one sheet of slide glass to be subjected to the treatment; a supply arm by which one sheet of slide glass to be subjected to the treatment is picked up from the storage unit and supplied onto the stage; a discharge arm by which the slide glass mounted on the stage is picked up and discharged in the storage unit; a moving unit operable to move the supply arm and the discharge arm in an integral manner so as to bring the supply arm or the discharge arm into proximity to each of the storage unit and the stage; and a control unit operable to control the supply arm, the discharge arm and the moving unit.

A digital slide scanning apparatus typically scans a single slide at a time. Some digital slide scanning apparatus have been modified to hold one or more slide racks so that the digital slide scanning apparatus can process tens or hundreds of glass slides. However, these systems are still limited in their capacity. Therefore, what is needed is a system and method that overcomes these significant problems found in the conventional systems as described above.

Accordingly, described herein is a slide rack carousel for use with a digital slide scanning apparatus that allows for continuous loading and unloading of slide racks into the carousel while the digital slide scanning apparatus is simultaneously digitizing glass slides. As used herein, the term "continuous load" and/or "continuous unload" means loading and unloading of slide racks into the carousel during scanning of a glass slide to generate a digital image of a portion of the glass slide. Advantageously, the slide rack carousel functions to allow for continuous loading and unloading and the slide rack carousel also functions to use the vibration generated by operation of the apparatus to cause the glass slides to move into more stable positions within their respective slide rack in the slide rack carousel and to cause the slides racks to move into more stable positions within their respective slide rack slots in the slide rack carousel.

Also, the housing of the digital scanning apparatus has no door, which results in at least a portion of the carousel always being accessible to an operator in order to facilitate continuous loading and eliminate additional vibration caused by a door. The slide rack carousel also includes a multi-color status indicator for each rack slot.

Accordingly, in an embodiment a digital slide scanning apparatus carousel for holding a plurality of glass slide racks includes a base having a lower surface, an upper surface and an exterior edge, the exterior edge of the base being generally circular from a top view perspective. The carousel also includes a plurality of rack spacers extending upward from the base. Adjacent pairs of rack spacers define a rack slot bordered on three sides by the base, a first side of a first rack spacer and a second side of a second rack spacer. Each rack spacer, respectively, includes a first rack stopper on a first side of the rack spacer, a second rack stopper on a second side of the rack spacer. At least a portion of the upper surface of the carousel base angles downward from a more external position on the base toward a more central position on the base. Additionally, the base is configured to rotate <NUM> degrees in either direction.

In an embodiment, a digital slide scanning apparatus carousel for holding a plurality of glass slide racks includes a base having a lower surface, an upper surface and a circular shaped exterior edge, the upper surface having an angled central portion and a flat exterior portion. The carousel also includes a plurality of rack spacers extending upward from the base, wherein adjacent pairs of rack spacers define a rack slot bordered on three sides by the upper surface of the base, a first side of a first rack spacer and a second side of a second rack spacer. Each rack spacer respectively comprises a first rack stopper on a first side of the rack spacer and a second rack stopper on a second side of the rack spacer. The carousel also includes a motor configured to drive the base <NUM> degrees in either direction.

In an embodiment, the motor is configured to drive a rotor <NUM> degrees in either direction and the rotor is in contact with a belt such that rotation of the rotor in a first direction under control of the motor causes the belt to move the base in the first direction.

In an embodiment, the lower surface of the base includes a cutout and the carousel also comprises three or more v-wheel bearings configured to stabilize the base during rotation. At least one of the v-wheel bearings is adjustable in an embodiment.

Other features and advantages of the present invention will become more readily apparent to those of ordinary skill in the art after reviewing the following detailed description and accompanying drawings.

The structure and operation of the present invention will be understood from a review of the following detailed description and the accompanying drawings in which like reference numerals refer to like parts and in which:.

Certain embodiments disclosed herein provide for a slide rack carousel configured to hold plural slide rack of different heights and from different manufactures. The slide rack carousel allows for continuous slide rack loading and unloading while glass slides are being scanned by the digital slide scanning apparatus. After reading this description it will become apparent to one skilled in the art how to implement the invention in various alternative embodiments and alternative applications. However, although various embodiments of the present invention will be described herein, it is understood that these embodiments are presented by way of example only, and not limitation. As such, this detailed description of various alternative embodiments should not be construed to limit the scope or breadth of the present invention as set forth in the appended claims.

<FIG> is a perspective view diagram illustrating an example slide rack carousel base <NUM> according to an embodiment of the invention. In the illustrated embodiment the base <NUM> is substantially circular and is in the form of a ring <NUM>. The base <NUM> has a lower surface and an upper surface and at least a portion of the upper surface angles downward toward the center of the ring <NUM>.

<FIG> is a top view diagram illustrating an example slide rack carousel base <NUM> according to an embodiment of the invention. In the illustrated embodiment, the upper surface of the base <NUM> has an angled portion that is more centrally located and the upper surface of the base <NUM> also has a flat portion that is more externally located near the perimeter of the circular shaped base <NUM> that is in the form of a ring <NUM>.

<FIG> is a perspective view diagram illustrating an example cross section of a slide rack carousel base <NUM> according to an embodiment of the invention. In the illustrated embodiment, the based has a cutout <NUM> in the lower surface, the cutout <NUM> is configured to allow the base <NUM> to be secured to a drive that is powered by a motor and thereby moves the base <NUM><NUM> degrees in either the left or right direction.

<FIG> is a side view diagram illustrating an example cross section of a slide rack carousel base <NUM> according to an embodiment of the invention. As shown in the illustrated embodiment, the base <NUM> is in the form of a ring <NUM>.

<FIG> is a side view diagram illustrating an example cross section of one side of a slide rack carousel base <NUM> according to an embodiment of the invention. In the illustrated embodiment, a portion of the upper surface of the carousel base <NUM> is flat and the perimeter edge of the upper surface of the carousel base <NUM> has a bevel. The flat portion of the upper surface is near the perimeter of the upper surface of the carousel base <NUM>. The bevel facilitates loading of slide racks <NUM> into the slide rack slot <NUM> of the slide rack <NUM> carousel. Additionally, a different portion of the upper surface of the carousel base <NUM> is angled at an angle of <NUM>°. Advantageously, at least a portion of the upper surface of the carousel base <NUM> is angled and the degree of the angle, θ°, may range from <NUM>° to <NUM>°, or even higher up to <NUM>°. As previously discussed, when a slide rack <NUM> is positioned on the angled upper surface of the carousel base <NUM>, any vibration induced or other movement of the slide rack <NUM> is biased toward the center of the carousel where slide rack stoppers <NUM> prevent further movement of the slide rack <NUM>. Additionally, the individual slides in the slide rack <NUM> may also experience vibration induced movement or other movement and the angled position of the slide rack <NUM> in which an individual slide is disposed also positions the individual slide at an angle such that movement of the individual slide is biased toward the center of the carousel where the end of the slide rack <NUM> prevents further movement of the slide rack <NUM>.

Additionally, the carousel base <NUM> is supported by a machine base <NUM> that also supports the digital pathology scanning apparatus. One or more v-wheel bearings <NUM> are positioned to engage a surface of the cutout <NUM> in order to maintain the position of the carousel base <NUM> as it is turned by a belt that is positioned in the belt recess <NUM>.

<FIG> is a perspective view diagram illustrating an example slide rack carousel base <NUM> engaged with a carousel belt <NUM> for turning the carousel base <NUM> according to an embodiment of the invention. In the illustrated embodiment, the carousel base <NUM> is supported by the machine base <NUM>. The machine base <NUM> also supports a carousel motor <NUM> that is configured to be controlled by a processor and turn the carousel belt <NUM> that is engaged with carousel base <NUM>. The turning of the carousel belt <NUM> advantageously causes the carousel to rotate. The carousel motor <NUM> is configured to turn the carousel belt <NUM> in two directions such that the carousel can be rotated left or right.

<FIG> is a perspective view diagram illustrating an example slide rack carousel base <NUM> with slide rack spacers <NUM> engaged with a carousel belt <NUM> for turning the carousel base <NUM> according to an embodiment of the invention.

<FIG> is a perspective view diagram illustrating an example slide rack carousel base <NUM> engaged with a plurality of v-wheel bearings <NUM> according to an embodiment of the invention. In the illustrated embodiment, a plurality of v-wheel bearings <NUM> are positioned to engage with or be proximal to an interior surface of the cutout <NUM> of the carousel base <NUM>. In the illustrated embodiment, there are three v-wheel bearings <NUM> that are advantageously positioned in an opposing triangular orientation to secure the carousel base <NUM> from lateral movement while allowing the carousel base <NUM> to rotate. In one embodiment, at least one of the v-wheel bearings <NUM> is an adjustable v-wheel bearing <NUM> to allow the initial positioning of the carousel between the opposing v-wheel bearings <NUM>, while the other v-wheel bearings <NUM> may be non-adjustable v-wheel bearings <NUM>. In alternative embodiments, two or more of the v-wheel bearings <NUM> may be adjustable. In one embodiment, the v-wheel bearings <NUM> are secured to the machine base <NUM> (not shown). In one embodiment, the adjustable v-wheel bearing is manually adjustable and in an alternative, embodiment, the adjustable v-wheel bearing is adjusted under control of a processor.

<FIG> is an alternative perspective view diagram illustrating the example slide rack carousel base <NUM> of <FIG> engaged with a plurality of v-wheel bearings <NUM> according to an embodiment of the invention.

<FIG> is a top view diagram illustrating an example slide rack carousel base <NUM> supported by a machine base <NUM> and engaged with a carousel belt <NUM> for turning the carousel base <NUM> according to an embodiment of the invention. In the illustrated embodiment, the carousel belt <NUM> is positioned in a belt recess <NUM> of the carousel base <NUM> and the carousel belt <NUM> extends around the carousel base <NUM> and the carousel belt <NUM> also extends around at least one rotor <NUM> that is turned by a carousel motor <NUM> (not shown). Advantageously, the carousel motor <NUM> may operate under control of a processor to turn the rotor <NUM> in a left direction or a right direction and thereby turn the carousel belt <NUM> in the left direction or the right direction and thereby rotate the carousel base <NUM> in the left direction or the right direction.

In alternative embodiments, the carousel base <NUM> may have a drive system that employs a belt or another mechanism such as direct gearing or direct drive. Advantageously, the drive system may be paired with a variety of types of bearing systems to implement movement of the carousel base <NUM>.

<FIG> is a perspective view diagram illustrating an example slide rack carousel base <NUM> with rack spacers <NUM> according to an embodiment of the invention. In the illustrated embodiment, the base <NUM> has an upper surface with a more external flat portion and a more central angled portion upon which the slide racks <NUM> are to be positioned. The carousel includes a plurality of rack spacers <NUM> that extend upward from the upper surface of the base <NUM>. Adjacent rack spacers <NUM> form a rack slot <NUM> that is configured to receive a wide variety of different types of slide racks <NUM> made by different manufactures. In one embodiment, the slide racks <NUM> may be of different heights and/or widths and still fit within at least one rack slot <NUM>.

<FIG> is a top view diagram illustrating an example slide rack carousel base <NUM> with rack spacers <NUM> according to an embodiment of the invention. In the illustrated embodiment, each rack spacer <NUM> comprises a first rack stopper <NUM> on a first side and a second rack stopper <NUM> on a second side. Each of the first and second rack stoppers <NUM> of a single rack spacer <NUM> face different rack slots <NUM>. Accordingly, a first rack stopper <NUM> of a first rack spacer <NUM> and a second rack stopper <NUM> of a second rack spacer <NUM> face each other. Advantageously, the distance between the first rack stopper <NUM> and the second rack stopper <NUM> of a particular rack slot <NUM> is less than the width of a slide rack <NUM>. In this fashion, the combination of opposing first rack stopper <NUM> and second rack stopper <NUM> prevent a slide rack <NUM> from traveling any further toward the center of the slide rack <NUM> carousel. In one embodiment, at least one of the facing first and second rack stoppers <NUM> include a rack stopper gap <NUM> configured to facilitate detection of the presence of a slide rack <NUM>.

In one embodiment, one or more of the slide rack stoppers <NUM> is configured with a detector <NUM> oriented in a slide rack <NUM> stopper gap <NUM> that is positioned to determine if a slide rack <NUM> occupies the rack slot <NUM> in which the slide rack <NUM> stopper <NUM> is positioned. The digital scanning apparatus may receive a signal from one or more detectors <NUM> of a single rack slot <NUM> and based on the signal or signals, make a determination regarding the presence or absence of a slide rack <NUM> in the particular rack slot <NUM>. Additionally, the digital scanning apparatus may also illuminate a multi-color status indicator light associated with the particular rack slot <NUM> based on the determination regarding the presence or absence of a slide rack <NUM> in the particular rack slot <NUM>.

<FIG>, <FIG> are perspective, top and side view diagrams illustrating an example slide rack <NUM> with glass slides <NUM> according to an embodiment of the invention. In the illustrated embodiment, the slide rack <NUM> if from a first manufacturer.

<FIG>, <FIG> are perspective, top and side view diagrams illustrating an example slide rack <NUM> with glass slides <NUM> according to an embodiment of the invention. In the illustrated embodiment, the slide rack <NUM> if from a second manufacturer.

<FIG> and <FIG> are perspective and top view diagrams illustrating an example slide rack carousel base <NUM> with rack spacers <NUM> and different height slide racks <NUM> with glass slides <NUM> according to an embodiment of the invention. In the illustrated embodiments, the carousel comprises a base having a flat upper surface portion <NUM> and an angled upper surface portion <NUM>. Rack spacers <NUM> are attached to the upper surface of the base <NUM> and extend upward from the upper surface of the base <NUM>. Adjacent rack spacers <NUM> define a rack slot <NUM> into which a slide rack <NUM> can be positioned such that slide rack <NUM> rests primarily on the angled portion of the upper surface of the base <NUM>. Glass slides <NUM> occupy various slots in the slide rack <NUM> and the glass slides <NUM> are advantageously positioned at an angle in accordance with the angle of the upper surface of the base <NUM>. Additionally, the carousel comprises a central ring <NUM> that is secured to an upper portion of each of the plurality of rack spacers <NUM>.

In one embodiment, a digital slide scanning apparatus carousel for holding a plurality of glass slide <NUM> racks <NUM> includes a base having a lower surface, an upper surface and an exterior edge. The exterior edge of the base <NUM> is generally circular in shape when viewed from a top view perspective. The carousel also includes a plurality of rack spacers <NUM> extending upward from the base <NUM>. This configuration causes adjacent pairs of rack spacers <NUM> to define a rack slot <NUM> bordered on three sides by the base <NUM>, a first side of a first rack spacer <NUM> and a second side of a second rack spacer <NUM>. Each rack spacer <NUM> comprises a first rack stop on a first side and a second rack stop on a second side. Additionally, at least a portion of the upper surface of the base <NUM> angles downward from a more external position on the base <NUM> toward a more central position on the base <NUM> and the angle is at least <NUM> degree. This angle advantageously causes any vibration imposed on the glass slides <NUM> in the carousel to urge the glass slides <NUM> further into their respective slide racks <NUM>. Additionally, the base <NUM> is configured to rotate <NUM> degrees in either direction.

The digital slide scanning apparatus carousel may also include a motor configured to rotate the carousel in either direction. In one embodiment, the angled portion of the upper surface of the base <NUM> is angled at least <NUM> degrees. Additionally, in one embodiment each rack stop comprises a slide rack <NUM> detector configured to detect the presence of a slide rack <NUM> in the slide rack slot <NUM>.

In one embodiment, the carousel is configured with fifteen separate rack slots <NUM>. Advantageously, in one embodiment, each rack slot <NUM> may be numbered and include a multi-color status indicator light. In one embodiment, an exterior portion of the upper surface of the base <NUM> that is adjacent to the exterior edge is substantially flat and the angled portion of the upper surface of the base <NUM> is more central than the substantially flat portion. In one embodiment, the base <NUM> forms a ring shape.

Advantageously, in on embodiment, each of the plurality of rack spacers <NUM> is secured to the base <NUM>. And in one embodiment, the carousel also includes a ring <NUM> that is secured to an upper portion of each of the plurality of rack spacers <NUM>. Additionally, in one embodiment a first rack spacer <NUM> and a second rack spacer <NUM> define a first rack slot <NUM> and the first rack stopper <NUM> of the first rack spacer <NUM> faces the second rack stopper <NUM> of the second rack spacer <NUM>. In this embodiment, a distance between a first rack stopper <NUM> and the second rack stopper <NUM> is less than a width of a slide rack <NUM>. This advantageously causes a slide rack <NUM> disposed at an angle on the upper surface of the base <NUM>, to be biased for vibration induced movement toward the center of the carousel, with such potential vibration induced movement prevented by the combination of the first rack stopper <NUM> and the second rack stopper <NUM>.

The various embodiments described herein may be implemented using a digital pathology scanning device such as described with respect to <FIG>.

<FIG> is a block diagram illustrating an example processor enabled device <NUM> that may be used in connection with various embodiments described herein. Alternative forms of the device <NUM> may also be used as will be understood by the skilled artisan. In the illustrated embodiment, the device <NUM> is presented as a digital imaging device (also referred to as a digital slide scanning apparatus, digital slide scanner, scanner, scanner system or a digital imaging device, etc.) that comprises one or more processors <NUM>, one or more memories <NUM>, one or more motion controllers <NUM>, one or more interface systems <NUM>, one or more movable stages <NUM> that each support one or more glass slides <NUM> with one or more samples <NUM>, one or more illumination systems <NUM> that illuminate the sample, one or more objective lenses <NUM> that each define an optical path <NUM> that travels along an optical axis, one or more objective lens positioners <NUM>, one or more optional epi-illumination systems <NUM> (e.g., included in a fluorescence scanner system), one or more focusing optics <NUM>, one or more line scan cameras <NUM> and/or one or more area scan cameras <NUM>, each of which define a separate field of view <NUM> on the sample <NUM> and/or glass slide <NUM>. The various elements of the scanner system <NUM> are communicatively coupled via one or more communication busses <NUM>. Although there may be one or more of each of the various elements of the scanner system <NUM>, for simplicity in the description, these elements will be described in the singular except when needed to be described in the plural to convey the appropriate information.

The one or more processors <NUM> may include, for example, a central processing unit ("CPU") and a separate graphics processing unit ("GPU") capable of processing instructions in parallel or the one or more processors <NUM> may include a multicore processor capable of processing instructions in parallel. Additional separate processors may also be provided to control particular components or perform particular functions such as image processing. For example, additional processors may include an auxiliary processor to manage data input, an auxiliary processor to perform floating point mathematical operations, a special-purpose processor having an architecture suitable for fast execution of signal processing algorithms (e.g., digital signal processor), a slave processor subordinate to the main processor (e.g., back-end processor), an additional processor for controlling the line scan camera <NUM>, the stage <NUM>, the objective lens <NUM>, and/or a display (not shown). Such additional processors may be separate discrete processors or may be integrated with the processor <NUM>.

The memory <NUM> provides storage of data and instructions for programs that can be executed by the processor <NUM>. The memory <NUM> may include one or more volatile and/or nonvolatile computer-readable storage mediums that store the data and instructions, including, for example, a random access memory, a read only memory, a hard disk drive, removable storage drive, and the like. The processor <NUM> is configured to execute instructions that are stored in memory <NUM> and communicate via communication bus <NUM> with the various elements of the scanner system <NUM> to carry out the overall function of the scanner system <NUM>.

The one or more communication busses <NUM> may include a communication bus <NUM> that is configured to convey analog electrical signals and may include a communication bus <NUM> that is configured to convey digital data. Accordingly, communications from the processor <NUM>, the motion controller <NUM>, and/or the interface system <NUM> via the one or more communication busses <NUM> may include both electrical signals and digital data. The processor <NUM>, the motion controller <NUM>, and/or the interface system <NUM> may also be configured to communicate with one or more of the various elements of the scanning system <NUM> via a wireless communication link.

The motion control system <NUM> is configured to precisely control and coordinate XYZ movement of the stage <NUM> and the objective lens <NUM> (e.g., via the objective lens positioner <NUM>). The motion control system <NUM> is also configured to control movement of any other moving part in the scanner system <NUM>. For example, in a fluorescence scanner embodiment, the motion control system <NUM> is configured to coordinate movement of optical filters and the like in the epi-illumination system <NUM>.

The interface system <NUM> allows the scanner system <NUM> to interface with other systems and human operators. For example, the interface system <NUM> may include a user interface to provide information directly to an operator and/or to allow direct input from an operator. The interface system <NUM> is also configured to facilitate communication and data transfer between the scanning system <NUM> and one or more external devices that are directly connected (e.g., a printer, removable storage medium, etc.) or external devices such as an image server system, an operator station, a user station, and an administrative server system that are connected to the scanner system <NUM> via a network (not shown).

The illumination system <NUM> is configured to illuminate a portion of the sample <NUM>. The illumination system <NUM> may include, for example, a light source and illumination optics. The light source could be a variable intensity halogen light source with a concave reflective mirror to maximize light output and a KG-<NUM> filter to suppress heat. The light source could also be any type of arc-lamp, laser, or other source of light. In an embodiment, the illumination system <NUM> illuminates the sample <NUM> in transmission mode such that the line scan camera <NUM> and/or area scan camera <NUM> sense optical energy that is transmitted through the sample <NUM>. Alternatively, or additionally, the illumination system <NUM> may be configured to illuminate the sample <NUM> in reflection mode such that the line scan camera <NUM> and/or area scan camera <NUM> sense optical energy that is reflected from the sample <NUM>. Overall, the illumination system <NUM> is configured to be suitable for interrogation of the microscopic sample <NUM> in any known mode of optical microscopy.

In an embodiment, the scanner system <NUM> optionally includes an epi-illumination system <NUM> to optimize the scanner system <NUM> for fluorescence scanning. Fluorescence scanning is the scanning of samples <NUM> that include fluorescence molecules, which are photon sensitive molecules that can absorb light at a specific wavelength (excitation). These photon sensitive molecules also emit light at a higher wavelength (emission). Because the efficiency of this photoluminescence phenomenon is very low, the amount of emitted light is often very low. This low amount of emitted light typically frustrates conventional techniques for scanning and digitizing the sample <NUM> (e.g., transmission mode microscopy). Advantageously, in an optional fluorescence scanner system embodiment of the scanner system <NUM>, use of a line scan camera <NUM> that includes multiple linear sensor arrays (e.g., a time delay integration ("TDI") line scan camera) increases the sensitivity to light of the line scan camera by exposing the same area of the sample <NUM> to each of the multiple linear sensor arrays of the line scan camera <NUM>. This is particularly useful when scanning faint fluorescence samples with low emitted light.

Accordingly, in a fluorescence scanner system embodiment, the line scan camera <NUM> is preferably a monochrome TDI line scan camera. Advantageously, monochrome images are ideal in fluorescence microscopy because they provide a more accurate representation of the actual signals from the various channels present on the sample. As will be understood by those skilled in the art, a fluorescence sample <NUM> can be labeled with multiple florescence dyes that emit light at different wavelengths, which are also referred to as "channels.

Furthermore, because the low and high end signal levels of various fluorescence samples present a wide spectrum of wavelengths for the line scan camera <NUM> to sense, it is desirable for the low and high end signal levels that the line scan camera <NUM> can sense to be similarly wide. Accordingly, in a fluorescence scanner embodiment, a line scan camera <NUM> used in the fluorescence scanning system <NUM> is a monochrome <NUM> bit <NUM> linear array TDI line scan camera. It should be noted that a variety of bit depths for the line scan camera <NUM> can be employed for use with a fluorescence scanner embodiment of the scanning system <NUM>.

The movable stage <NUM> is configured for precise X-Y axes movement under control of the processor <NUM> or the motion controller <NUM>. The movable stage may also be configured for movement in a Z axis under control of the processor <NUM> or the motion controller <NUM>. The moveable stage is configured to position the sample in a desired location during image data capture by the line scan camera <NUM> and/or the area scan camera. The moveable stage is also configured to accelerate the sample <NUM> in a scanning direction to a substantially constant velocity and then maintain the substantially constant velocity during image data capture by the line scan camera <NUM>. In an embodiment, the scanner system <NUM> may employ a high precision and tightly coordinated X-Y grid to aid in the location of the sample <NUM> on the movable stage <NUM>. In an embodiment, the movable stage <NUM> is a linear motor based X-Y stage with high precision encoders employed on both the X and the Y axis. For example, very precise nanometer encoders can be used on the axis in the scanning direction and on the axis that is in the direction perpendicular to the scanning direction and on the same plane as the scanning direction. The stage is also configured to support the glass slide <NUM> upon which the sample <NUM> is disposed.

The sample <NUM> can be anything that may be interrogated by optical microscopy. For example, a glass microscope slide <NUM> is frequently used as a viewing substrate for specimens that include tissues and cells, chromosomes, DNA, protein, blood, bone marrow, urine, bacteria, beads, biopsy materials, or any other type of biological material or substance that is either dead or alive, stained or unstained, labeled or unlabeled. The sample <NUM> may also be an array of any type of DNA or DNA-related material such as cDNA, RNA or protein that is deposited on any type of slide or other substrate, including any and all samples commonly known as microarrays. The sample <NUM> may be a microtiter plate, for example a <NUM>-well plate. Other examples of the sample <NUM> include integrated circuit boards, electrophoresis records, petri dishes, film, semiconductor materials, forensic materials, and machined parts.

Objective lens <NUM> is mounted on the objective positioner <NUM> which, in an embodiment, may employ a very precise linear motor to move the objective lens <NUM> along the optical axis defined by the objective lens <NUM>. For example, the linear motor of the objective lens positioner <NUM> may include a <NUM> nanometer encoder. The relative positions of the stage <NUM> and the objective lens <NUM> in XYZ axes are coordinated and controlled in a closed loop manner using motion controller <NUM> under the control of the processor <NUM> that employs memory <NUM> for storing information and instructions, including the computer-executable programmed steps for overall operation of the scanning system <NUM>.

In an embodiment, the objective lens <NUM> is a plan apochromatic ("APO") infinity corrected objective with a numerical aperture corresponding to the highest spatial resolution desirable, where the objective lens <NUM> is suitable for transmission mode illumination microscopy, reflection mode illumination microscopy, and/or epi-illumination mode fluorescence microscopy (e.g., an Olympus 40X, <NUM>. 75NA or 20X, <NUM> NA). Advantageously, objective lens <NUM> is capable of correcting for chromatic and spherical aberrations. Because objective lens <NUM> is infinity corrected, focusing optics <NUM> can be placed in the optical path <NUM> above the objective lens <NUM> where the light beam passing through the objective lens becomes a collimated light beam. The focusing optics <NUM> focus the optical signal captured by the objective lens <NUM> onto the light-responsive elements of the line scan camera <NUM> and/or the area scan camera <NUM> and may include optical components such as filters, magnification changer lenses, and/or the like. The objective lens <NUM> combined with focusing optics <NUM> provides the total magnification for the scanning system <NUM>. In an embodiment, the focusing optics <NUM> may contain a tube lens and an optional 2X magnification changer. Advantageously, the 2X magnification changer allows a native 20X objective lens <NUM> to scan the sample <NUM> at 40X magnification.

The line scan camera <NUM> comprises at least one linear array of picture elements ("pixels"). The line scan camera may be monochrome or color. Color line scan cameras typically have at least three linear arrays, while monochrome line scan cameras may have a single linear array or plural linear arrays. Any type of singular or plural linear array, whether packaged as part of a camera or custom-integrated into an imaging electronic module, can also be used. For example, a <NUM> linear array ("red-green-blue" or "RGB") color line scan camera or a <NUM> linear array monochrome TDI may also be used. TDI line scan cameras typically provide a substantially better signal-to-noise ratio ("SNR") in the output signal by summing intensity data from previously imaged regions of a specimen, yielding an increase in the SNR that is in proportion to the square-root of the number of integration stages. TDI line scan cameras comprise multiple linear arrays. For example, TDI line scan cameras are available with <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or even more linear arrays. The scanner system <NUM> also supports linear arrays that are manufactured in a variety of formats including some with <NUM> pixels, some with <NUM> pixels, and others having as many as <NUM> pixels. Similarly, linear arrays with a variety of pixel sizes can also be used in the scanner system <NUM>. The salient requirement for the selection of any type of line scan camera <NUM> is that the motion of the stage <NUM> can be synchronized with the line rate of the line scan camera <NUM> so that the stage <NUM> can be in motion with respect to the line scan camera <NUM> during the digital image capture of the sample <NUM>.

The image data generated by the line scan camera <NUM> is stored in a portion of the memory <NUM> and processed by the processor <NUM> to generate a contiguous digital image of at least a portion of the sample <NUM>. The contiguous digital image can be further processed by the processor <NUM> and the processed contiguous digital image can also be stored in the memory <NUM>.

In an embodiment with two or more line scan cameras <NUM>, at least one of the line scan cameras <NUM> can be configured to function as a focusing sensor that operates in combination with at least one of the line scan cameras <NUM> that is configured to function as an imaging sensor. The focusing sensor can be logically positioned on the same optical axis as the imaging sensor or the focusing sensor may be logically positioned before or after the imaging sensor with respect to the scanning direction of the scanner system <NUM>. In an embodiment with at least one line scan camera <NUM> functioning as a focusing sensor, the image data generated by the focusing sensor is stored in a portion of the memory <NUM> and processed by the one or more processors <NUM> to generate focus information to allow the scanner system <NUM> to adjust the relative distance between the sample <NUM> and the objective lens <NUM> to maintain focus on the sample during scanning. Additionally, in an embodiment the at least one line scan camera <NUM> functioning as a focusing sensor may be oriented such that each of a plurality of individual pixels of the focusing sensor is positioned at a different logical height along the optical path <NUM>.

In operation, the various components of the scanner system <NUM> and the programmed modules stored in memory <NUM> enable automatic scanning and digitizing of the sample <NUM>, which is disposed on a glass slide <NUM>. The glass slide <NUM> is securely placed on the movable stage <NUM> of the scanner system <NUM> for scanning the sample <NUM>. Under control of the processor <NUM>, the movable stage <NUM> accelerates the sample <NUM> to a substantially constant velocity for sensing by the line scan camera <NUM>, where the speed of the stage is synchronized with the line rate of the line scan camera <NUM>. After scanning a stripe of image data, the movable stage <NUM> decelerates and brings the sample <NUM> to a substantially complete stop. The movable stage <NUM> then moves orthogonal to the scanning direction to position the sample <NUM> for scanning of a subsequent stripe of image data, e.g., an adjacent stripe. Additional stripes are subsequently scanned until an entire portion of the sample <NUM> or the entire sample <NUM> is scanned.

For example, during digital scanning of the sample <NUM>, a contiguous digital image of the sample <NUM> is acquired as a plurality of contiguous fields of view that are combined together to form an image strip. A plurality of adjacent image strips are similarly combined together to form a contiguous digital image of a portion of the sample <NUM> or the entire sample <NUM>. The scanning of the sample <NUM> may include acquiring vertical image strips or horizontal image strips. The scanning of the sample <NUM> may be either top-to-bottom, bottom-to-top, or both (bi-directional) and may start at any point on the sample. Alternatively, the scanning of the sample <NUM> may be either left-to-right, right-to-left, or both (bi-directional) and may start at any point on the sample. Additionally, it is not necessary that image strips be acquired in an adjacent or contiguous manner. Furthermore, the resulting image of the sample <NUM> may be an image of the entire sample <NUM> or only a portion of the sample <NUM>.

In an embodiment, computer-executable instructions (e.g., programmed modules or other software) are stored in the memory <NUM> and, when executed, enable the scanning system <NUM> to perform the various functions described herein. In this description, the term "computer-readable storage medium" is used to refer to any media used to store and provide computer executable instructions to the scanning system <NUM> for execution by the processor <NUM>. Examples of these media include memory <NUM> and any removable or external storage medium (not shown) communicatively coupled with the scanning system <NUM> either directly or indirectly (e.g., via a network).

<FIG> illustrates a line scan camera having a single linear array <NUM>, which may be implemented as a charge coupled device ("CCD") array. The single linear array <NUM> comprises a plurality of individual pixels <NUM>. In the illustrated embodiment, the single linear array <NUM> has <NUM> pixels. In alternative embodiments, linear array <NUM> may have more or fewer pixels. For example, common formats of linear arrays include <NUM>, <NUM>, and <NUM> pixels. The pixels <NUM> are arranged in a linear fashion to define a field of view <NUM> for the linear array <NUM>. The size of the field of view varies in accordance with the magnification of the scanner system <NUM>.

<FIG> illustrates a line scan camera having three linear arrays, each of which may be implemented as a CCD array. The three linear arrays combine to form a color array <NUM>. In an embodiment, each individual linear array in the color array <NUM> detects a different color intensity, (e.g., red, green, or blue). The color image data from each individual linear array in the color array <NUM> is combined to form a single field of view <NUM> of color image data.

<FIG> illustrates a line scan camera having a plurality of linear arrays, each of which may be implemented as a CCD array. The plurality of linear arrays combine to form a TDI array <NUM>. Advantageously, a TDI line scan camera may provide a substantially better SNR in its output signal by summing intensity data from previously imaged regions of a specimen, yielding an increase in the SNR that is in proportion to the square-root of the number of linear arrays (also referred to as integration stages). A TDI line scan camera may comprise a larger variety of numbers of linear arrays. For example common formats of TDI line scan cameras include <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and even more linear arrays.

Claim 1:
A slide rack carousel for holding a plurality of glass slide racks (<NUM>) for use in a digital slide scanning apparatus, the slide rack carousel comprising:
a slide rack carousel base (<NUM>) having a lower surface, an upper surface, and an exterior edge which is adjacent to an exterior portion of the upper surface of the slide rack carousel base (<NUM>), wherein the exterior edge of the slide rack carousel base (<NUM>) is generally circular from a top view perspective,
wherein at least a portion of the upper surface of the slide rack carousel base (<NUM>) is angled downward towards a center of the slide rack carousel base (<NUM>), and wherein the angle is at least <NUM> degree, wherein the upper surface is configured to receive at least one glass slide rack of the plurality of glass slide racks (<NUM>) to bias the at least one slide rack towards the center of the slide rack carousel base (<NUM>), and
wherein the slide rack carousel base (<NUM>) is configured to rotate <NUM> degrees in at least one direction.