Optical fiber switch for flow cytometer

Abstract

A fiber optic switch for a flow cytometer workstation that includes an input fiber, a first output fiber, a second output fiber, an input housing, an output housing and a selector. The input fiber and output fibers each include a transmission end. The input housing includes an input optical cavity. The selector changes relative position of the input housing and the output housing between a first position and a second position. The first position is defined by axial alignment between input transmission end of the input fiber and output transmission end of the first output fiber. The second position is defined by the axial alignment of the input transmission end of the input fiber and the output transmission end of the second output fiber.

Description

OPTICAL FIBER SWITCH FOR FLOW CYTOMETERCross-Reference to Related Application

[0001] This application is being filed on July 24, 2025, as a PCT International application and claims the benefit of and priority to U.S. Provisional Application No. 63 / 676,121, filed July 26, 2024; the disclosure of which is hereby incorporated by reference in its entirety.Background

[0002] In a flow cytometer, a light source, such as a laser, is directed toward a sample which produces light scattering. The scattered light is collected by detectors as optical signals and can be analyzed to determine various sample attributes. The optical signals can be carried to other components and eventually converted to electrical signals. As a result of changing flow cytometer capabilities, improvements to managing optical signals are needed.Summary

[0003] In general terms, this disclosure is directed to an Optical Fiber Switch for Flow Cytometer. In certain embodiments, and by non-limiting example, a fiber optic switch for a flow cytometer workstation includes an input fiber, a first output fiber, a second output fiber, an input housing, an output housing, and a selector. The input fiber includes an input transmission end. The first and second output fibers each have an output transmission end. The input housing includes an input optical cavity. The input optical cavity houses the input transmission end of the input fiber. The output housing includes first and second output optical cavities. The first output optical cavity houses the transmission end of the first output fiber. The second output optical cavity houses the transmission end of the second output fiber. The selector changes relative position of the input housing and the output housing between a first position and a second position. The first position is defined by axial alignment between the input transmission end of the input fiber and the output transmission end of the first output fiber. The second position is defined by the axial alignment of the input transmission end of the input fiber and the output transmission end of the second output fiber.

[0004] In certain embodiments, and by non-limiting example a fiber optic switch for a flow cytometer workstation includes an input fiber, a first output fiber, a second output fiber, and a selector. The input fiber includes an input transmission end within the fiber optic switch. The first and second output fibers each have an outputtransmission end within the fiber optic switch. The selector controls a signal path. The selector is changeable between directing a signal from the input transmission end of the input fiber to the output transmission end of the first output fiber and directing the signal from the input transmission end of the input fiber to the output transmission end of the second output fiber.

[0005] In certain embodiments, and by non-limiting example a flow cytometer workstation includes a first flow cytometer, a second flow cytometer, and a fiber optic switch. The fiber optic switch includes an input fiber, a first output fiber, a second output fiber, and a selector. The input fiber includes an input transmission end within the fiber optic switch. The first and second output fibers each have an output transmission end within the fiber optic switch. The selector controls a signal path. The selector is changeable between directing a signal from the input transmission end of the input fiber to the output transmission end of the first output fiber and directing the signal from the input transmission end of the input fiber to the output transmission end of the second output fiber.Brief Description of the Drawings

[0006] FIG. 1 is a schematic view of a first example flow cytometer workstation.

[0007] FIG. 2 is a schematic view of an example fiber optic switch for a flow cytometer workstation.

[0008] FIG. 3 is a schematic view of another example fiber optic switch design.

[0009] FIG. 4 is a schematic view of another example fiber optic switch design.

[0010] FIG. 5 is a schematic view of another example fiber optic switch design.

[0011] FIG. 6 is a schematic view of another example fiber optic switch design.

[0012] FIG. 7 is a perspective view of another example fiber optic switch design.

[0013] FIG. 8 is a perspective view of another example fiber optic switch design.

[0014] FIG. 9 is a perspective view of another example fiber optic switch design.

[0015] FIG. 10 is another perspective view of the example fiber optic switch design of FIG. 9.

[0016] FIG. 11 is a focused cross-sectional side view of the example fiber optic switch design of FIG. 9, taken along an input transmission axis.

[0017] FIG. 12 is a focused cross-sectional side view of an output housing from the example fiber optic switch design of FIG. 9, taken along the interface between an input housing and the output housing.Detailed Description

[0018] Various embodiments will be described in detail with reference to the drawings, wherein like reference numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the appended claims.

[0019] Certain aspects of the present disclosure relate to fiber optic switches that are used to change where an input signal(s) is directed. In certain examples, the input signal(s) is directable to at least two different outputs. In certain examples, the outputs lead to different laboratory equipment, such as a flow cytometer. In certain examples, the fiber optic switch may transition a signal between two or more flow cytometers. For example, where one output is for conventional flow cytometry and another is for spectral flow cytometry7. An example conventional flow cytometer is described in WO2023179206A1, which is hereby incorporated in its entirety7.

[0020] Fiber optics are used to transmit data between various parts of a flow cytometer. In certain examples, fiber optics are used to transmit data between an optical bench and a wavelength-division multiplexer. Unlike in telecommunications applications, where wavelength ranges are narrow, flow cytometer fiber optics require a much wider range of wavelengths. As an example, a telecommunications optical fiber may transmit wavelengths between 1520- 161 Onm, whereas a flow cytometer optical fiber may transmit wavelengths ranging between 300-1200nm. As a result, typical switch designs in telecommunications applications are not ideal due to issues with chromatic aberration caused by lenses used in refraction based switches. Another difference between telecommunications fiber optics and flow cytometer fiber optics is the fiber ty pe and the core size of the fiber. Flow cytometer fiber optics rely on highly multimode fiber optics with cores sizes ranging between 300 and 500pm, while many telecommunications applications use single mode fiber optics with core sizes around 8- 10 pm.

[0021] FIG. 1 shows a schematic example flow cytometer workstation 10 that includes a first housing 20, a second housing 30, an optical bench 40, a first signal processor 50, a second signal processor 60, an input fiber 70, a first output fiber 80, a second output fiber 90, and a switch 100. In the example shown, the first housing 20 houses the optical bench 40 and the first signal processor 50. In certain examples, thefirst housing 20 is a first flow cytometer and the second housing 30 is a second flow cytometer. In certain examples, the various components are held within a single housing. In other examples, the various components may be modular and separate from each other.

[0022] In certain examples, the optical bench 40 includes a laser, a forward scatter detector, and a side scatter detector. In certain examples, the first signal processor 50 includes a wavelength-division multiplexer as part of a conventional flow cytometer. In certain examples, the second signal processor 60 includes a wavelength-division multiplexer as part of a spectral flow cytometer.

[0023] FIG. 2 shows a schematic example of the switch 100. The switch 100 represents a fiber optic switch capable of directing an input signal coming from the input fiber 70 to either the first output fiber 80 or the second output fiber 90. In certain examples, the input fiber 70, the first output fiber 80, and the second output fiber 90 each include multiple fibers within a single cable. In certain examples, the first and second output fibers 80, 90 have the same number of individual fibers as the input fiber 70. A selector 130 selectively directs the input signal to either the first or second output fibers 80, 90. As described below, there are many different possible selector devices / mechanisms. Numerous different switch solutions will be discussed throughout this disclosure, and switch 100 may encompass any / all aspects of the described solutions and / or combinations of the described solutions.

[0024] FIG. 3 shows a schematic example switch 200 that uses a mirror 210 and lenses 220 to transmit light signals from the input fiber 70 to either the first or second output fibers 80, 90 by rotating mirror 210 between a first position 210a and a second position 210b. In the example shown, mirror 210 is a flat mirror. When mirror 210 is in the first position 210a, the light signal travels from the input fiber 70 into a lens 220 where the light is separated by wavelength, then that light reflects off the mirror 210 and travels into another lens 220 where the light is focused back together before entering the first output fiber 80. Similarly, when the mirror 210 is in the second position 210b, the light signal travels from the input fiber 70 into a lens 220 where the light is separated by wavelength, then that light reflects off the mirror 210 and travels into another lens 220 where the light is grouped back together before entering the second output fiber 90. In other examples, the mirror 210 may move in and out of a light path extending between the input fiber 70 and the first output fiber 80 such that when the mirror is absent, the light signal travels from the input fiber 70 to the firstoutput fiber 80 without need for a mirror, and when the mirror is present, the light signal from the input fiber 70 reflects off the mirror and is directed to the second output fiber 90. In other examples, the input fiber 70 may move while the minor 210 and output fibers 80, 90 remain stationary. In other examples, the output fibers 80, 90 may move while the input fiber 70 and mirror 210 remain stationary.

[0025] As shown, the switch 200, includes a selector 230 that is capable of moving the mirror 210 between the first position 210a and the second position 210b. Alternatively, selector 230 could change the angle of input fiber 70 to accomplish the same effect. The selector 230 could be any number of devices capable of switching, or causing a switch, between two or more states. For example, the selector 230 may be a solenoid, a relay, a transistor, a microcontroller, a magnetic reed switch, a rocker, a toggle, pressure switch, etc. These are only a few examples of ways to perform switching. The selector 230 may be controlled by software, programs, external devices, or any other suitable means.

[0026] For highly multimode fibers transmitting a wide range of wavelengths, switch 200 can suffer from issues of chromatic aberration due to the use of lenses 220 and the different wavelengths of light having different focal lengths. In telecommunications applications, chromatic aberration is less of an issue because the wavelength ranges are narrow.

[0027] FIG. 4 shows another example switch 300 that avoids the potential chromatic aberration issues of switch 200. Switch 300 uses only mirrors to direct the light signal from the input fiber 70 to either of the output fibers 80, 90. Switch 300 includes an input mirror 310 and an output mirror 320. The input mirror 310 has a first position 310a in which light is directed to the output mirror 320 at a first position 320a. When the output mirror 320 is in the first position, the light coming from the input fiber is directed to the first output fiber 80. Relatedly, when the input mirror 310 is at a second position 310b, the light is directed to mirror 320 at a second position 320b. When the output mirror 320 is in the second position, the light coming from the input fiber 70 is directed to the second output fiber 90. The mirrors 310, 320 are reflective collimating mirrors. In certain examples, the first and second position of either / both mirrors 310, 320, may be positioned by rotation about a specific axis. For example, mirror 310 may change between the first and second positions 310a, 310b by rotating mirror 310 about an input axis 350. In certain examples, the first and second positions 310a, 310b of the first mirror may be accomplished by using two different minors. Incertain examples, the first and second positions 320a, 320b of the second mirror may be accomplished by using two different mirrors. Mirrors 310 and 320 are parabolic in shape in order to avoid aberration. FIG. 4 is shown as schematic, 2-D images, but it should be appreciated that the mirrors described above may be paraboloids.

[0028] As show n, the switch 300, includes a selector 330 that is capable of moving the mirrors 310, 320 between the first positions 310a, 320a and the second positions 310b, 320b. Alternatively, selector 330 could change the angle of input fiber 70 or output fibers 80, 90, or a combination of changing fiber angles and mirror positions to accomplish the same effect. The selector 330 could be any number of devices capable of switching, or causing a switch, between two or more states. For example, the selector 330 may be a solenoid, a relay, a transistor, a microcontroller, a magnetic reed switch, a rocker, a toggle, pressure switch, etc. These are only a few examples of ways to perform switching. The selector 330 may be controlled by softw are, programs, external devices, or any other suitable means.

[0029] FIG. 5 shows another example switch 400. The switch 400 uses a single mirror to direct light signals from the input fiber to either of the output fibers 80, 90. The switch 400 includes a mirror 410 that has an elliptical curve. The elliptical curve of mirror 410 enables the possibility of using only a single mirror to direct light signals to the output fibers by rotating the mirror 410 about an input axis 450. A transmission end 72 of the input fiber 70 is mounted at a first focal point of the ellipsoid of the mirror 410, which images the transmission end 72 of the input fiber 70 with a magnification of lx on a second focal point. When the mirror 410 is rotated around the input axis 450 of the input fiber 70, the second focal point draw s a trajectory of a circle. Multiple output fibers (e.g., first and second output fibers 80, 90) can be placed on this circular trajectory to receive the light. For example, when a transmission end 82, 92 of either output fiber 80, 90 is at the second focal point, the light leaving the transmission end 72 of the input fiber 70 is reflected to the transmission end 82, 92 of either output fiber 80, 90. FIG. 5 is shown as a schematic, 2-D image, but it should be appreciated that the mirror described above may be ellipsoid.

[0030] As shown, the switch 400, includes a selector 430 that is capable of moving the mirror 410 between a first position 410a, and a second position 410b. Alternatively, selector 430 could change the angle of input fiber 70 or output fibers 80, 90, or a combination of changing fiber angles and mirror positions to accomplish the same effect. The selector 430 could be any number of devices capable of switching, and / orcausing a switch, between two or more states. For example, the selector 430 may be a solenoid, a relay, a transistor, a microcontroller, a magnetic reed switch, a rocker, a toggle, pressure switch, etc. These are only a few examples of ways to perform switching. The selector 430 may be controlled by software, programs, external devices, or any other suitable means.

[0031] FIG. 6 shows a schematic example of a switch 500 that uses face coupling between the input fiber 70 and the output fibers 80. 90. The switch 500 aligns the transmission end 72 of the input fiber 70 with the transmission end 82, 92 of either output fiber 80, 90. In the schematic shown, a selector 530 switches, and / or causes a switch, between output fibers 80, 90 coupled with the input fiber 70. The switch can move either the input fiber 70 or output fibers 80. 90 such that the desired fibers are aligned along an input axis 550. The selector 530 causes motion between the input fiber 70 and the output fibers 80, 90 that is transverse to the input axis 550.

[0032] FIG. 7 shows an example of translational motion being used between a group of input fibers A and different groups of output fibers B. FIG. 8 shows an example of rotational motion between a single input fiber C and a number of output fibers D. FIGS. 7 and 8 show different examples of how face coupling may be used to transmit an input signal(s) to an output signal (s) directly.

[0033] FIGS. 9-12 show an example switch 600 that uses face coupling as shown in the schematic example of FIG. 6. The switch 600 includes an input housing 610 that houses the transmission end 72 of the input fiber 70. An output housing 620 is positioned adjacent the input housing 610 and houses the transmission ends 82, 92 of the output fibers 80, 90.

[0034] In certain examples, the input housing 610 is adjustably fixed to a switch platform 640. In certain examples, the input housing 610 includes an upper portion 612 and a lower portion 614 that together create an input optical cavity 616 for the input fiber 70 that extends between a first input wall 611 and a second input wall 613. In certain examples, the upper portion 612 is removable from the lower portion 614 and securable to the lower portion 614 through the use of fasteners. In certain examples, the input housing 610 is adjustably positioned using first and second input housing adjustments 660, 662. As shown, the first input housing adjustment 660 controls a vertical height of the input housing 610. The second input housing adjustment 662 controls angular alignment of a transmission axis 650. The transmission axis 650extends centrally through the input fiber 70 in the direction of the input signal extending from the input fiber 70.

[0035] In certain examples, the output housing 620 is slidably mounted to a switch frame 680. The switch frame 680 includes a base 682 mounted to the switch platform 640 and first and second vertical side walls 684, 686. In certain examples, the output housing 620 slides transverse the transmission axis 650, such that the transmission axis 650 aligns with a center of either the transmission end 82 of the first output fiber 80 in a first position 632 or the transmission end 92 of the second output fiber 90 in a second position 634. The output housing 620 is slidable between the first and second positions632, 634 on a slide rail 638. The slide rail 638 enables the output housing 620 to move about a slide axis 639. The slide rail 638 prevents movement of the output housing 620 about any other axis. The first and second positions 632, 634 are adjustable using first and second position adjustments 633, 635. The first and second position adjustments633, 635 adjust the distance that the output housing 620 moves on the slide rail 638 when moving between the first position 632 and the second position 634. In certain examples, the first position adjustment 633 is mounted to the first sidewall 684 and the second position adjustment 635 is mounted to the second sidewall 686. The first and second position adjustments 633, 635 are mounted within slots on the first and second sidewalls.

[0036] In certain examples, the output housing 620 includes an upper portion 622 and a lower portion 624 that together create first and second output optical cavities 626, 628 for housing the transmission ends 82, 92 of the respective output fibers 80, 90 that extend between a first output wall 621 and a second output wall 623. In certain examples, the input optical cavity 616 and / or the first and second output optical cavities 626, 628 include v-grooves in the lower portions of the input and output housings in order to center the optical fiber in the cavit . In certain examples, the output fibers 80, 90 are joined together by a sleeve 637 and / or a collar 641 as the output fibers 80, 90 enter the output housing 620.

[0037] In certain examples, the first input wall 611 and the first output wall 621 are positioned adjacent each other such that the first input wall 611 has a face that is parallel to a face of the first output wall 621. In certain examples, there is a small space between the input housing 610 and the output housing 620 such that the first output wall 621 of the output housing 620 may slide in close proximity of the first input wall 611 of the input housing 610 without added friction.

[0038] In certain examples, there is a cavity 618 at the transmission axis 650 and at the interface between the input and output housings 610, 620 for index matching fluid, such that the input signal is able to transmit to the output fiber with the index matching fluid filling a gap G formed between the transmission end 72 of the input fiber 70 and the transmission end 82, 92 of either output fiber 80, 90. In certain examples, a portion of the cavity 618 is formed by the input housing and another portion of the cavity 618 is formed by the output housing. As shown, the cavity 618 is formed by neighboring channels on each of the input housing and output housing. In certain examples, the first and second output optical cavities 626, 628 extend into the cavity 618. In certain examples, the cavity 618 includes a top opening. In certain examples, there is no space between the first input wall 611 of the input housing 610 and first output wall 621 of the output housing 620 such that when the output housing 620 slides about the slide rail 638, the output housing 620 rubs against the input housing 610 but the cavity’ 618 remains between the input fiber 70 and output fibers 80, 90. In certain examples, the first and second output cavities 626. 628 share the same cavity but include separate v- grooves.

[0039] In certain examples, the gap G between input and output transmission ends is less than or equal to 0.08mm with a coupling efficiency greater than or equal to 98%. The coupling efficiency is a measure of the percentage of transmitted light that makes it from the input fiber to the output fiber. In certain examples, the gap G between the input and output transmission ends is greater than 08mm and less than or equal to 0. 19mm and the coupling efficiency is less than 98% but greater than or equal to 95%.

[0040] In certain examples, there may be a radial offset between the transmission axis of the input fiber and a central axis of the output fiber. In certain examples, the radial offset is less than or equal to 0.01mm and the coupling efficiency is greater than or equal to 98%. In certain examples, the radial offset is greater than 0.01mm but less than or equal to 0.02mm and the coupling efficiency is less than 98% but greater than or equal to 95%. In certain examples, the switch 600 has an average variation in coupling efficiency of 1.4%.

[0041] In certain examples, movement between the first position 632 and the second position 634 is performed by a selector 630. The selector 630 may be a solenoid, a relay, a transistor, a microcontroller, a magnetic reed switch, a rocker, a toggle, pressure switch, etc. As shown, the selector 630 is a solenoid controlled by a toggle switch 636. In other examples, the selector 630 may be controlled by software,programs, external devices, wireless signals, or any other suitable means. A circuit board 670 links the selector 630 with the toggle switch 636.

[0042] In certain examples, an operation for switching signals between output fibers includes receiving a signal to change from a first output fiber to a second output fiber; sending the signal to a solenoid; activating the solenoid and driving an output housing from the first position to the second position about a slide rail with the solenoid; sending a light transmission from an input fiber to the second output fiber. A similar operation could be done to go from the second output fiber to the first output fiber.

[0043] The various embodiments described above are provided by way of illustration only and should not be construed to limit the claims attached hereto. Those skilled in the art will readily recognize various modifications and changes that may be made without following the example embodiments and applications illustrated and described herein, and without departing from the full scope of the following claims.

Claims

WHAT IS CLAIMED IS:

1. A fiber optic switch for a flow cytometer workstation comprising: an input fiber including an input transmission end; a first output fiber; a second output fiber, the first and second output fibers each having an output transmission end; an input housing including an input optical cavity, the input optical cavity housing the input transmission end of the input fiber; an output housing including first and second output optical cavities, the first output optical cavity housing the transmission end of the first output fiber, the second output optical cavity housing the transmission end of the second output fiber; and a selector that changes relative position of the input housing and the output housing between a first position and a second position, the first position defined by axial alignment between the input transmission end of the input fiber and the output transmission end of the first output fiber, the second position defined by the axial alignment of the input transmission end of the input fiber and the output transmission end of the second output fiber.

2. The fiber optic switch of claim 1, wherein the input housing includes an upper portion and a lower portion separable from each other and forming the input optical cavity between them, each of the upper and lower portions extending between a first input wall and an opposite second input wall.

3. The fiber optic switch of claim 2, wherein the input optical cavity extends through the first input wall and through the second input wall.

4. The fiber optic switch of claim 2, wherein the output housing includes an upper portion and a lower portion separable from each other and forming the first and second output optical cavities between them, each of the upper and lower portions extending between a first output wall and an opposite second output wall.

5. The fiber optic switch of claim 4, wherein the first and second output optical cavities extend through the first output wall and through the second output wall.

6. The fiber optic switch of claim 4, wherein the first input wall and the first output wall are parallel to each other and adjacent each other.

7. The fiber optic switch of any one of claims 1-6, wherein the first and second output cavities extend parallelly through the output housing.

8. The fiber optic switch of any one of claims 1-7, wherein the switch further includes first and second input housing adjustments, wherein the first input housing adjustment controls a height of the input housing, and the second input housing adjustment controls angular alignment of the input housing relative to the output housing along a transmission axis.

9. The fiber optic switch of any one of claims 1-8, wherein the switch further includes first and second position adjustments, wherein the first position adjustment controls the position of the output housing in the first position, wherein the second position adjustment controls the position of the output housing in the second position.

10. The fiber optic switch of any one of claims 1-9, wherein the selector is a solenoid.

11. The fiber optic switch of any one of claims 1-10, wherein the first and second output fibers are carried within a collar before entering the first and second output optical cavity housings.

12. The fiber optic switch of any one of claims 1-11, wherein a cavity is formed by neighboring channels in each of the input housing and output housing.

13. The fiber optic switch of claim 12, wherein the input optical cavity and the first and second output optical cavities intersect with the cavity, wherein index matching fluid is used within the cavity.

14. The fiber optic switch of any one of claims 1-13, wherein a gap between the input and output transmission ends is less than or equal to 0.08mm with a coupling efficiency greater than or equal to 98%.

15. A fiber optic switch for a flow cytometer workstation comprising: an input fiber including an input transmission end within the fiber optic switch; a first output fiber; a second output fiber, the first and second output fibers each having an output transmission end within the fiber optic switch; and a selector for controlling a signal path, the selector changeable between directing a signal from the input transmission end of the input fiber to the output transmission end of the first output fiber and directing the signal from the input transmission end of the input fiber to the output transmission end of the second output fiber.

16. The flow cytometer workstation of claim 15, wherein the first and second output fibers have a fiber core size between 300 and 500pm.

17. The flow cytometer workstation of any one of claims 15-16, wherein the input fiber and the first and second output fibers are capable of transmitting light in wavelengths ranging between 300-1200nm.

18. A flow cytometer workstation comprising: a first flow cytometer; a second flow cytometer; a fiber optic switch comprising: an input fiber including an input transmission end within the fiber optic switch;a first output fiber; a second output fiber, the first and second output fibers each having an output transmission end within the fiber optic switch; and a selector for controlling a signal path, the selector changeable between directing a signal from the input transmission end of the input fiber to the output transmission end of the first output fiber and directing the signal from the input transmission end of the input fiber to the output transmission end of the second output fiber.

19. The flow cytometer workstation of claim 18, wherein the first flow cytometer is a spectral flow cytometer and the second flow cytometer is a conventional flow cytometer.

20. The flow cytometer workstation of any one of claims 18-19, wherein the input transmission end of the input fiber directly couples to the first and second output transmission ends of the first and second output fibers.

Images