Multi-channel optical pressure sensor

Abstract

The invention provides a multi-channel optical pressure sensor. The multi-channel optical pressure sensor includes: at least one LED configured to generate light having a first spectrum and a second spectrum; a plurality of sensors including a first sensor coupled to the at least one LED via at least one first optical fiber and a second sensor coupled to the at least one LED via at least one second optical fiber; and a detector module coupled to the first sensor and the second sensor. The detector module includes at least one lens and an image sensor configured to sense light received from the at least one lens. The multi-channel optical pressure sensor further includes at least one hardware processor configured to determine a first pressure measured at the first sensor and a second pressure measured at the second sensor based at least in part on the light sensed by the image sensor.

Description

Technical Field

[0001] The present disclosure relates to a multi-channel optical pressure sensor. Background Art

[0002] Fluid pumps, such as blood pumps, are used in the medical field for a wide range of applications and purposes. An intravascular blood pump is a pump that can be advanced through a patient's vascular distribution (i.e., veins and / or arteries) to a location in the patient's heart or elsewhere within the patient's circulatory system. For example, an intravascular blood pump can be inserted via a catheter and positioned to span a heart valve. The intravascular blood pump is typically placed at the end of a catheter. Once in place, the pump can be used to assist the heart and pump blood through the circulatory system, and thereby temporarily reduce the workload on the patient's heart, such as to enable the heart to recover after a heart attack. An exemplary intravascular blood pump is available from Johnson & Johnson (ABIOMED) of Danvers, Massachusetts, under the trade name A heart pump was purchased.

[0003] For example, such a pump may be positioned in a heart chamber, such as the left ventricle, to assist the heart. In this case, the blood pump may be inserted via the femoral artery with the aid of a hollow catheter and introduced upward and into the left ventricle of the patient's heart. From this location, the blood pump inlet draws in blood, and the blood pump outlet discharges blood into the aorta. In this way, heart function may be replaced or at least assisted by operating the pump.

[0004] The intravascular blood pump is typically connected to a corresponding external heart pump controller that controls the heart pump (e.g., motor speed) and collects and displays operational data about the blood pump (e.g., heart signal level, battery temperature, blood flow rate, and tubing integrity). An exemplary heart pump controller is available from Johnson & Johnson under the trade name Automated Impella The controller may sound an alarm when an operational data value falls outside a predetermined value or range (e.g., if a leak, suction, and / or pump failure is detected). The controller may include a video display screen on which a circular user interface configured to display operational data and / or alarms is displayed. Summary of the invention

[0005] Systems and methods for a multi-channel optical pressure sensor are described herein. In some embodiments, the multi-channel optical pressure sensor can be incorporated into a heart pump. When the heart pump is positioned within the patient's heart, the multi-channel optical pressure sensor, when incorporated into the heart pump, can be used to sense, for example, differential pressure across an aortic valve. The differential pressure measurement can be used, for example, to calculate a blood flow rate through the heart pump during operation of the heart pump.

[0006] In some embodiments, a multi-channel optical pressure sensor is provided. The multi-channel optical sensor includes: at least one light emitting diode (LED); a plurality of sensors, including a first sensor coupled to the at least one LED via at least one first optical fiber and a second sensor coupled to the at least one LED via at least one second optical fiber; a detector module coupled to the first sensor and the second sensor, the detector module including at least one lens and an image sensor configured to sense light received from the at least one lens; and at least one hardware processor configured to determine a first pressure measured at the first sensor and a second pressure measured at the second sensor based at least in part on the light sensed by the image sensor.

[0007] In one aspect, the at least one LED comprises: a first LED configured to generate a first light having a first spectrum; and a second LED configured to generate a second light having a second spectrum. In one aspect, the first spectrum has a peak wavelength in the range of 550nm to 670nm, and the second spectrum has a peak wavelength in the range of 800nm ​​to 900nm. In one aspect, the first spectrum has a peak wavelength in the range of 550nm to 600nm. In one aspect, the peak wavelength of the first spectrum is 4 / 5 of the peak wavelength of the second spectrum. In one aspect, the first LED and / or the second LED is less than 1mm. In one aspect, the first LED and / or the second LED is a phosphor converted LED. In one aspect, the at least one LED comprises a single LED having a wide spectrum.

[0008] In one aspect, the sensor further includes a first optical element arranged between the at least one LED and the plurality of sensors. The first optical element is configured to receive the first light and the second light and output a third light and a fourth light, each of the third light and the fourth light having a third spectrum. In one aspect, the sensor further includes a second optical element coupled to the first optical element, the first sensor, and the detector module, and a third optical element coupled to the first optical element, the second sensor, and the detector module. In one aspect, the second optical element is configured to provide a first reflected light from the first sensor to the detector module, and the third optical element is configured to provide a second reflected light from the second sensor to the detector module.

[0009] In one aspect, the at least one lens comprises a planar lens. In one aspect, the planar lens comprises a set of D-shaped lenses having curved edges facing each other. In one aspect, the at least one lens is configured to reduce spherical aberration in the light received from the first sensor and the second sensor. In one aspect, the at least one lens is configured to amplify the light signal incident on the at least one lens. In one aspect, the magnification factor of the at least one lens is at least 1.1 and less than 3. In one aspect, the magnification factor is at least 1.1 and less than 2. In one aspect, the magnification factor is less than 1.5. In one aspect, the magnification factor is less than 1.3. In one aspect, the at least one lens includes at least two lenses that collectively amplify the light signal incident on the at least one lens. In one aspect, the at least two lenses include a first lens having a first focal length and a second lens having a second focal length different from the first focal length. In one aspect, each of the first lens and the second lens is a D-shaped lens having a curved edge, and the curved edges of the first lens and the second lens are arranged to face each other.

[0010] In one aspect, the detector module further includes a Fizeau disposed between the at least one lens and the image sensor. In one aspect, the image sensor includes a two-dimensional image sensor. In one aspect, the at least one lens and the Fizeau are configured to project the light received from the first sensor and the second sensor as two lines together on the two-dimensional image sensor. In one aspect, the two lines are two parallel lines. In one aspect, each of the two lines on the two-dimensional image sensor includes an interference pattern, and wherein determining a first pressure measured at the first sensor and a second pressure measured at the second sensor based at least in part on the light sensed by the image sensor includes determining the first pressure and the second pressure based on corresponding interference patterns.

[0011] In some embodiments, a cyclic support device is provided. The cyclic support device includes: a rotor; a motor configured to drive the rotor to rotate at one or more speeds; a first optical pressure sensor configured to detect a first pressure signal; a second optical pressure sensor configured to detect a second pressure signal; and at least one hardware processor. The at least one hardware processor is configured to determine a differential pressure signal based at least in part on the first pressure signal and the second pressure signal.

[0012] In one aspect, the at least one hardware processor is further configured to determine a flow rate through the cyclic support device based at least in part on the differential pressure signal. In one aspect, the cyclic support device further includes: a first light emitting diode (LED) coupled to the first optical pressure sensor and the second optical pressure sensor, the first LED being configured to generate a first light having a first spectrum; and a second LED coupled to the first optical pressure sensor and the second optical pressure sensor, the second LED being configured to generate a second light having a second spectrum. In one aspect, the first spectrum has a peak wavelength in the range of 550nm to 670nm, and the second spectrum has a peak wavelength in the range of 800nm ​​to 900nm. In one aspect, the first spectrum has a peak wavelength in the range of 550nm to 600nm. In one aspect, the peak wavelength of the first spectrum is 4 / 5 of the peak wavelength of the second spectrum. In one aspect, the first LED and / or the second LED is less than 1mm. In one aspect, the first LED and / or the second LED is a phosphor converted LED.

[0013] In one aspect, the cyclic support device further includes a first optical element, the first optical element is arranged to receive the first light and the second light and output a third light and a fourth light, each of the third lights having a third spectrum, the third light is provided to the first optical pressure sensor, and the fourth light is provided to the second optical pressure sensor. In one aspect, the cyclic support device further includes a second optical element coupled to the first optical element and the first optical pressure sensor and a third optical element coupled to the first optical element and the second optical pressure sensor. In one aspect, the cyclic support device further includes a detector module, wherein the second optical element is configured to provide a first reflected light from the first optical pressure sensor to the detector module, and the third optical element is configured to provide a second reflected light from the second optical pressure sensor to the detector module.

[0014] In one aspect, the cyclic support device further includes a detector module coupled to the first optical pressure sensor and the second optical pressure sensor. The detector module includes at least one lens and an image sensor configured to sense light received from the at least one lens. In one aspect, the at least one lens includes a planar lens. In one aspect, the planar lens includes a set of D-shaped lenses with curved edges facing each other. In one aspect, the at least one lens is configured to reduce spherical aberration in the light received from the first optical pressure sensor and the second optical pressure sensor. In one aspect, the at least one lens is configured to amplify the optical signal incident on the at least one lens. In one aspect, the magnification factor of the at least one lens is at least 1.1 and less than 3. In one aspect, the magnification factor is at least 1.1 and less than 2. In one aspect, the magnification factor is less than 1.5. In one aspect, the magnification factor is less than 1.3. In one aspect, the at least one lens includes at least two lenses that jointly amplify the optical signal incident on the at least one lens. In one aspect, the at least two lenses include a first lens having a first focal length and a second lens having a second focal length different from the first focal length. In one aspect, each of the first lens and the second lens is a D-shaped lens having a curved edge, and the curved edges of the first lens and the second lens are arranged to face each other.

[0015] In one aspect, the detector module further includes a Fizeau disposed between the at least one lens and the image sensor. In one aspect, the image sensor includes a two-dimensional image sensor. In one aspect, the at least one lens and the Fizeau are configured to project the light received from the first optical pressure sensor and the second optical pressure sensor as two lines together on the two-dimensional image sensor. In one aspect, the two lines are two parallel lines. In one aspect, each of the two lines on the two-dimensional image sensor includes an interference pattern, and the at least one hardware processor is further configured to: determine the first pressure measured at the first optical pressure sensor and the second pressure measured at the second optical pressure sensor by determining the first pressure and the second pressure based on the corresponding interference pattern, at least in part based on the light sensed by the image sensor, and determine the differential pressure signal based at least in part on the first pressure signal and the second pressure signal, including determining the differential pressure signal based on the first pressure and the second pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1A An illustrative circulation support device that may be used in accordance with some embodiments is shown.

[0017] Figure 1B Graphical instructions Figure 1A A circulatory support device positioned within a patient's heart.

[0018] Figure 1C Illustrated instructions include Figure 1A The ventricular support system of the circulatory support device.

[0019] Figure 2 A cyclic support device including a multi-channel optical pressure sensor is illustrated in accordance with some embodiments.

[0020] Figure 3 Components of a multi-channel optical pressure sensor system are illustrated in accordance with some embodiments.

[0021] Figure 4 A detector module for a multi-channel optical pressure sensor system according to some embodiments is schematically illustrated.

[0022] Figure 5 A process for generating an interferogram using a single channel optical pressure sensor system is schematically illustrated.

[0023] Fig. 6A The illustrated instructions can be found in Figure 5 Spectrum (top) and interferogram signal (bottom) of the broadband white light source used in the single-channel optical pressure sensor system.

[0024] Figure 6B Illustrated is a spectrum (top) and an interferogram signal (bottom) of a dual LED light source that may be used in a multi-channel optical pressure sensor system according to some embodiments.

[0025] Figure 6C Illustrated are the optical spectrum (top) and interferogram signal (bottom) of a dual wide spectrum LED light source that may be used in a multi-channel optical pressure sensor system according to some embodiments.

[0026] Fig. 7A Illustrate a display of an interferogram signal recorded using a two-dimensional image sensor of a multi-channel optical pressure sensor system, in accordance with some embodiments.

[0027] Figure 7B Illustration from Fig. 7A Interference pattern signal extracted from the image sensor data shown in .

[0028] Fig. 8A The lens design for a detector module including a symmetrical pair of D-shaped lenses according to some embodiments is schematically illustrated.

[0029] Figure 8BAn alternative lens design for a detector module including an asymmetric pair of D-shaped lenses according to some embodiments is schematically illustrated. DETAILED DESCRIPTION

[0030] A circulatory support device (also referred to herein as a "heart pump" or just a "pump") may include a catheter-based percutaneous device that provides hemodynamic support to a patient's heart. As will be appreciated, in order for a heart pump to function properly, it should be correctly positioned in the patient's heart with an inlet portion of the pump located in the left ventricle and an outlet portion of the pump located in the aorta, thereby spanning the aortic valve of the patient's heart. Figure 1A 1 , the heart pump 110 may include a pigtail 111, an inlet region 112, a cannula 113, a pressure sensor 114, an outlet region 115, a motor housing 116, and / or a catheter tube 117. The pigtail 111 may assist in stabilizing the heart pump 110 in the patient's heart. It should be appreciated that some embodiments of the heart pump 110 may not include the pigtail 111 and may stabilize the heart pump 110 in other ways or not stabilize the heart pump 110 at all. During operation, blood may be drawn into one or more openings in the inlet region 112 by a motor (not shown) disposed in the motor housing 116, directed through the cannula 113, and discharged through one or more openings in the outlet region 115. In some implementations, the pressure sensor 114 may include a flexible membrane integrated into the cannula 113. One side of the pressure sensor 114 may be exposed to the blood pressure on the outside of the cannula 113, and the other side may be exposed to the blood pressure inside the cannula 113. In some such embodiments, pressure sensor 114 may generate an electrical signal proportional to the difference between the pressure outside cannula 113 and the pressure inside cannula 113. In some embodiments, pressure sensor 114 may include an optical pressure sensor. Catheter tube 117 may provide a connection between heart pump 110 and a ventricular support system (in Figure 1C One or more fluid and / or electrical connections between one or more other devices (examples of which are shown in ).

[0031] like Figure 1B, the heart pump 110 can be positioned in the patient's heart 120. For example, the heart pump 110 can be percutaneously inserted into the ascending aorta 124 via the femoral artery 122, across the aortic valve 126, and into the left ventricle 128. In other embodiments, for example, the heart pump can be percutaneously inserted into the ascending aorta 124 via the axillary artery 123, across the aortic valve 126, and into the left ventricle 128. In other embodiments, for example, the heart pump can be inserted directly into the ascending aorta 124, across the aortic valve 126, and into the left ventricle 128. During operation, the heart pump 110 can entrain blood from the left ventricle 128 and discharge the blood into the ascending aorta 124. Thus, the heart pump 110 can perform some of the work normally done by the patient's heart 120. The hemodynamic effects of the cardiac pump may include increased cardiac output and improved coronary blood flow, which in turn lead to reduced left ventricular end-diastolic pressure, pulmonary capillary wedge pressure, myocardial workload, and oxygen consumption.

[0032] like Figure 1C As shown in FIG. 1 , the heart pump 110 may form part of the ventricular support system 100. The ventricular support system 100 may also include a controller 130 (e.g., an Automated Impella 140, a display 140, a flushing subsystem 150, a connector cable 160, a plug 170, and a repositioning unit 180. As shown, the controller 130 may include the display 140. The controller 130 monitors and controls the operation of the heart pump 110. During operation, the flushing subsystem 150 may be configured to deliver a flushing fluid to the heart pump 110 through the catheter tube 117 to prevent blood from entering the motor (not shown) within the motor housing 116. In some embodiments, the flushing fluid is a glucose solution (e.g., 5% glucose dissolved in water containing 25 IU / mL or 50 IU / mL heparin). The connector cable 160 may provide an electrical connection between the heart pump 110 and the controller 130. The plug 170 may connect the catheter tube 117, the flushing subsystem 150, and the connector cable 160. In some embodiments, the plug 170 includes a storage device (e.g., a memory) configured to store, for example, operating parameters to facilitate transferring the patient to another controller when necessary. Repositioning unit 180 may be used to reposition heart pump 110 within the patient's heart.

[0033] As shown, in some embodiments, the ventricular support system may include an irrigation subsystem 150 having a container 151, a supply line 152, an irrigation cassette 153, an irrigation valve disc 154, an irrigation line 155, a check valve 156, an accumulator 157, an injection filter 158, and a sidewall 159. For example, the container 151 may be a bag or a bottle. As will be appreciated, in other embodiments, the ventricular support system may not include an irrigation subsystem. In some embodiments, irrigation fluid may be stored in the container 151. The supply line 152 may provide a fluid connection between the container 151 and the irrigation cassette 153. The irrigation cassette 153 may control how the irrigation fluid in the container 151 is delivered to the heart pump 110. For example, the irrigation cassette 153 may include one or more valves for controlling the pressure and / or flow rate of the irrigation fluid. The irrigation valve disc 154 may include one or more pressure and / or flow sensors for measuring the pressure and / or flow rate of the irrigation fluid. As shown, the controller 130 can include a flush cassette 153 and a flush valve disc 154. A flush line 155 can provide a fluid connection between the flush valve disc 154 and the check valve 156. During flush fluid replacement, the accumulator 157 provides additional fill volume. In some embodiments, the accumulator 157 includes a flexible rubber diaphragm that provides additional fill volume with the aid of an expansion chamber. An injection filter 158 helps prevent bacterial contamination and air from entering the catheter tube 117. A sidewall 159 provides a fluid connection between the injection filter 158 and the plug 170.

[0034] Although shown as having separate irrigation lines and connector cables, it will be appreciated that in some embodiments, the ventricular support system may include a single connector having both fluid and electrical lines that may be connected to the AIC.

[0035] During operation, the controller 130 may be configured to receive measurements from the pressure sensor 114 and the flush valve disc 154 and control the operation of the motor (not shown) and flush cassette 153 within the motor housing 116. As noted above, the controller 130 may be configured to control and measure the pressure and / or flow rate of the flush fluid via the flush cassette 153 and flush valve disc 154. During operation, after the flush fluid exits the flush subsystem 150 through the sidewall 159, it may be directed through the flush lumen (not shown) within the catheter tube 117 and the plug 170. The catheter tube 117, the connector cable 160, and the sensor cable (not shown) within the plug 170 may provide an electrical connection between the pressure sensor 114 and the controller 130. The catheter tube 117, the connector cable 160, and the motor cable (not shown) within the plug 170 may provide an electrical connection between the motor within the motor housing 116 and the controller 130. During operation, the controller 130 may be configured to receive measurements from the pressure sensor 114 via a sensor cable (e.g., optical fiber) and control power delivered via a motor cable to the motor within the motor housing 116. By controlling the power delivered to the motor within the motor housing 116, the controller 130 may be operable to control the speed of the motor within the motor housing 116.

[0036] Various modifications may be made to ventricular support system 100 and one or more of its components. For example, one or more additional sensors may be added to heart pump 100. In another example, a signal generator may be added to heart pump 100 to generate a signal indicative of the rotational speed of the motor within motor housing 116. As another example, one or more components of ventricular support system 100 may be separate. For example, display 140 may be incorporated into another device that communicates with controller 130 (e.g., wired or via one or more cables).

[0037] As described herein, a heart pump (e.g., heart pump 110) may include a pressure sensor 114 (e.g., an optical pressure sensor) that is configured to detect pressure within the aorta of a patient's heart when the heart pump is properly positioned. The pressure signal sensed by pressure sensor 114 may be used, at least in part, to determine that the heart pump is correctly positioned within the patient's heart and / or to determine a blood flow rate through the heart pump when in operation. For example, the pressure signal may be used in conjunction with a motor current signal received from a motor current sensor (not shown) and a set of stored values ​​to determine a flow rate through the heart pump. Based on the pressure signal measuring the pressure in the aorta and the set of stored values, the differential pressure across the aortic valve may also be indirectly determined.

[0038] The inventors have recognized and appreciated that incorporating one or more additional pressure sensors into the heart pump 110 can be beneficial, for example, for directly sensing pressure in both the aorta and the left ventricle, without having to infer pressure in the left ventricle based on a pressure sensor signal sensed in the aorta, as discussed above. The use of multiple pressure sensors is also referred to herein as implementing a multi-channel pressure sensor. Figure 2 The diagram illustrates an embodiment of the heart pump 200 in which the second pressure sensor 210 is arranged near the inlet region 112. When properly positioned within the patient's heart, the second pressure sensor 210 can be configured to measure a pressure sensor signal for determining left ventricular blood pressure. In such an embodiment, an additional sensor cable (e.g., an optical fiber) can be placed within the catheter tube 117 to provide a connection between the second pressure sensor 210 and a controller (e.g., controller 130).

[0039] The inventors have recognized and appreciated that housing multiple pressure sensors within a heart pump may be beneficial in providing lower power and / or smaller sensors than pressure sensors used in some conventional heart pumps, e.g., including pressure sensor 114. Additionally, using optically based pressure sensors may have advantages over electronic or other types of pressure sensors, including, but not limited to, their smaller size, their small or negligible pressure drift, and their durability. Figure 3 A multi-channel pressure sensor system 300 designed in accordance with some embodiments of the present technology is schematically illustrated. The system 300 includes a light source 310 and a plurality of optical sensors (e.g., a first sensor 340 and a second sensor 360) coupled via optical fibers and one or more optical elements. In the exemplary system 300, the light source 310 includes two light emitting diodes (LEDs) (i.e., a first LED 312 and a second LED 314) configured to output light having different spectra. As described in more detail below, the spectra of light output from the first LED 312 and the second LED 314 may be selected so that their combined output has some characteristics similar to white light produced, for example, by a tungsten filament lamp. In some embodiments, the size of the LED may be less than 1 mm. Such characteristics may facilitate the use of lower power LED light sources to perform multi-channel optical pressure sensing in a heart pump in accordance with the technology described herein.

[0040] As shown, the system 300 includes a plurality of optical elements arranged between a light source 310 and a plurality of sensors (e.g., sensors 340, 360). A first optical element 320 is arranged to receive light from a first LED 312 and a second LED 314. In some embodiments, the first optical element 320 is implemented as a splitter that mixes the light from the first LED 312 and the second LED 314 and provides the light at its output to a second optical element 330 and a third optical element 350. The light provided as input to the second optical element 330 and the third optical element 350 may have a blended or "mixed" spectrum from the light output from the first LED 312 and the second LED 314, and may have half the power of the light provided as input from the light source 310 to the first optical element 320. By mixing the light from the first LED 312 and the second LED 314, the first optical element provides light having a spectrum that includes some characteristics in common with white light, which may provide a less efficient (e.g., tungsten-based) light source. It should be appreciated that other types of light sources and / or optical components may alternatively be used to produce light for use with some embodiments. For example, a single low-power light source 310 may be used instead that is configured to produce light having multiple spectra or complex spectra that include some characteristics in common with white light (e.g., light having a wide spectrum, such as an ultra-wide LED). In such an embodiment, a first optical element 320 configured to mix light from multiple light sources (e.g., LED 312 and LED 314) may not be required, and light output from the single light source may be provided directly to the second optical element 330 and the third optical element 350 via one or more optical fibers.

[0041] In some embodiments, the second optical element 330 may be implemented as a splitter that provides the combined spectral light output from the first optical element 320 to the first sensor 340. The first sensor 340 may be configured as a reflective element such that at least some of the light provided to the first sensor 340 is reflected back by the second optical element 330, which provides the reflected light as input to the detector module 370. Similarly, the third optical element 350 may be configured as a splitter that provides the mixed spectral light output from the first optical element 320 to the second sensor 360. The second sensor 360 may be configured as a reflective element such that at least some of the light provided to the second sensor 360 is reflected back by the third optical element 350, which provides the reflected light as input to the detector module 370. In this manner, the reflected light signals provided by the first sensor 340 and the second sensor 360 are further processed by the components of the detector module 370. In some embodiments, a first optical fiber coupled between the second optical element 330 and the detector module 370 and a second optical fiber coupled between the third optical element 350 and the detector module 370 may be coupled to the detector module 370 via connectors configured to arrange the first optical fiber and the second optical fiber in close proximity to each other.

[0042] As shown, the detector module 370 may include one or more lenses 372 (e.g., planar lenses, aspherical lenses, biconvex lenses, etc.), a Fizeau 374, and an image sensor 376. In some embodiments, the lenses 372 may be implemented as a pair of D-shaped lenses facing each other, as described in further detail herein. In some embodiments, the lenses 372 may be configured to provide amplification of the optical signal transmitted through the lenses 372. In some embodiments, the amplification may be provided by implementing the lenses 372 as a pair of asymmetric D-shaped lenses facing each other, as described in further detail herein. The lenses 372 may be used to reduce spherical aberration, thereby enabling multiple channels of light reflected from the sensor to be spatially separated and represented on the detector as two (or more) parallel or nearly parallel lines with limited crosstalk. The light received by the lenses 372 is provided as input to the Fizeau 374. The Fizeau 374 may be implemented as two mirrors with a spatially varying dielectric layer disposed therebetween. Light entering Fizeau 374 may resonate at specific locations on the spatially varying dielectric layer to form a beam captured by detector 376, such as Fig. 7AIn some embodiments, the image sensor 376 may be configured as a two-dimensional image sensor on which multiple light channels are detected corresponding to the interference pattern of the reflected light signals from the first sensor 340 and the second sensor 360. The system 300 may further include at least one hardware processor 380 configured to analyze the signals captured by the image sensor 376 to determine the pressure sensed by each of the first sensor 340 and the second sensor 360, for example, based on the interference pattern signals captured by the image sensor 376. In some embodiments, the at least one hardware processor 380 may be implemented as described above in conjunction with Figure 1C A portion of controller 130 is depicted.

[0043] Figure 4 The schematic diagram illustrates the arrangement of components of the detector module 370 according to some embodiments. As shown, the detector module 370 includes a connector 410, which is configured to receive a signal from the above-mentioned combination. Figure 3 376. The optical fibers of the second optical element 330 and the third optical element 350 described. The connector 410 can be configured to arrange the incoming optical fibers in close proximity to each other. The two light beams output from the connector 410 are provided to the lens 372 to focus the light on the Fizeau 374, which redirects the light onto the surface of the image sensor 376. In some embodiments, the connector 410 is movable in a plane parallel to the lens 372 to adjust the focus of the light beam on the image sensor 376. As shown, the lens 372 can be implemented as a set of D-shaped lenses with curved edges oriented toward each other. The lens 372 can be configured to reduce spherical aberration that would exist when, for example, a rod lens is used.

[0044] Figure 5 Schematic diagrams illustrate a process for performing interferometry using an optical system such as those described herein. Figure 5 In the example, a white light source (e.g., a tungsten lamp) is used as a light source (e.g., Figure 3 310 in FIG. 3 ). However, it will be appreciated that other light sources (e.g., LEDs 312, 314) may be used instead. As shown, light generated by the source is provided as incident light I0 to a sensor (e.g., Figure 3 As shown, the sensor can be implemented as a transducer sensing interferometer. r Provided to a detector module (e.g., detector module 370) that includes an optical wedge (e.g., Fizeau 374), which is used to generate an interferogram signal (e.g., on an image sensor 376). The central peak of the interferogram signal may be tracked and / or otherwise used to determine the pressure value sensed by the sensor.

[0045] As discussed herein, the inventors have recognized and appreciated that some conventional white light sources generate considerable amounts of heat and use a large amount of power, which limits their use in certain implementations, including as a light source for a multi-channel optical pressure sensor in a heart pump. Thus, in some embodiments, one or more lower power light sources may be used to provide light having some properties similar to white light. For example, as described above in conjunction with Figure 3 As described with the system 300 shown in FIG. 1 , two LED sources configured to produce light having different spectra may be used.

[0046] Fig. 6A A graph showing the spectrum of light output by a white light source (top graph) and a graph of the corresponding interferogram signal recorded using the white light source (bottom graph). As shown, a conventional white light source has a broadband spectrum that produces an interferogram signal with a well-defined central region and small side lobes. Such an interferogram signal is ideal for determining the pressure sensed by a coupled optical pressure sensor. Figure 6B A graph showing the spectrum of light output by two narrowband LED sources (top graph) and a graph of the corresponding interferogram signal recorded using the two LED sources (bottom graph). The spectrum of light produced by the first LED source may have a lower peak wavelength (e.g., in the range of 550nm to 650nm), and the spectrum of light produced by the second LED source may have a higher peak wavelength (e.g., in the range of 800nm ​​to 900nm). In some embodiments, the spectrum of light produced by the first LED source has a peak wavelength in the range of 550nm to 610nm, and the spectrum of light produced by the second LED source has a peak wavelength in the range of 820nm to 850nm. In some embodiments, the peak wavelength of the first LED source is 4 / 5 of the peak wavelength of the second LED source.

[0047] like Figure 6B As shown in the bottom graph of , the interferogram signal produced by using two narrowband LED sources has a similar Fig. 6A Some characteristics of the interferogram signal produced by the broadband white light source shown in . For example, Figure 6B The interferogram signal shown in Fig. 6A When the lateral envelope line adjacent to the central portion of the signal drops sufficiently to enable tracking of the central portion of the signal relative to the other portions of the signal, the interferogram signal shown in 6B may be similar to the central portion of the interferogram signal shown in 6B and the lateral envelope line distinguishing the central region of the signal from the other portions. Fig. 6A As shown in and as combined above Figure 5 The interferogram signal is used in a similar manner to the process described in the demonstration. Figure 6C The diagram illustrates the interference pattern produced by two LEDs with broad spectrum. Figure 6C As shown in the bottom graph of , the interferogram signal generated by the two wide spectrum LED sources is closer to the interferogram generated by the tungsten lamp. In some embodiments, the lateral envelope of the interferogram signal can be substantially attenuated. Therefore, some embodiments mimic the use of a broadband white light source by using multiple narrowband and lower power LED sources, which when used in combination produce an interferogram signal that can be used in a multi-channel optical pressure sensor (e.g., for a heart pump). In some embodiments, one or more characteristics (e.g., amplitude, position) of the central peak of the central portion of the interferogram signal can be used to determine the pressure value sensed by the corresponding pressure sensor associated with the interferogram signal. It should be understood that in some embodiments, more than two light sources (e.g., LEDs) can be used, and the embodiments are not limited in this regard. Therefore, although a dual-channel optical pressure sensor system is shown and described herein, any multi-channel (e.g., two or more channels) optical pressure sensor system can be implemented using techniques similar to those described herein. In embodiments when more than two channels are used, more than two light sources can be beneficial so that the power of the optical signal provided to each of the sensors is sufficient to produce a reliable interferogram signal.

[0048] Fig. 7A Schematic diagram illustrating a representation of a signal generated by a two-dimensional image sensor (e.g., Figure 3 7. Display of an image of an interferogram signal captured by the image sensor 376 (shown in ). As shown, the interferogram signals captured by the image sensor for each of the corresponding optical sensors are represented as lines. For example, a first interferogram signal corresponding to reflected light from sensor 340 may be represented as line 710, and a second interferogram signal corresponding to reflected light from sensor 360 may be represented as line 720. As described herein, the components of the detector module may enable the interferogram signals represented as lines 710 and 720 to be spatially distinguishable and separable (e.g., with no crosstalk or with limited crosstalk). It should be appreciated that Fig. 7A Only a small portion of the image sensor shown in FIG. 1 is shown being utilized, demonstrating the feasibility of using more than two channels according to the techniques described herein when desired. For example, in some embodiments, up to 6 channels, 8 channels, or 10 channels may be used. Figure 7B , the intensity of the interference pattern signal can be extracted from the captured image sensor signal into the interference pattern signal. As described above, based at least in part on the extracted interference pattern signal, the pressure sensed by the corresponding sensor can be determined.

[0049] Fig. 8ASchematically illustrates components of a detector module that may be used to detect an interferogram signal associated with the described optical pressure sensor, according to some embodiments. Figure 4 The detector module 370 shown in FIG. Fig. 8A The detector module shown in FIG. 4 may include a lens 372 configured to receive one or more light beams (eg, for Figure 4 ). Lens 372 can be configured to focus light on Fizeau 374, which can redirect the light onto the surface of image sensor 376.

[0050] Fizeau 374 may be adjustable so that the cavity length range of the Fizeau may be fine-tuned to the cavity length range of the sensing interferometer that may change over time. Fine-tuning the total range of the Fizeau to fit the total range of the sensing interferometer may produce a maximum detected signal on the image sensor 376. For example, the Fizeau 374 may have a spatially varying cavity length between 14000nm and 19000nm, and the sensing interferometer may have a cavity length of 15000nm. In such an example, a location along the Fizeau 374 where the cavity length of the Fizeau is equal to 15000nm may produce a maximum interferometer signal on the image sensor 376. The inventors have recognized and appreciated that the cavity length of the Fizeau may depend, at least in part, on the angle at which the incident light beam travels through the interferometer. For example, as the angle increases, the cavity length may change so that for a particular point on the Fizeau 374, there may be some incident light energy perpendicular to the Fizeau (e.g., at 0° or 90°) and some incident light energy at a certain angle. Because the incident light energy arrives at different angles, the resulting interference pattern signal observed by sensor 376 may correspond to the sum of all of the signals across the range of angles, which may reduce the contrast of the sensed signal.

[0051] Similar to Figure 4 The lens design shown in Fig. 8A The design of lens 372 shown in FIG. 3 may be implemented as a set of D-shaped lenses having curved edges oriented toward each other. Fig. 8A In the example of FIG. 4 , the set of D-shaped lenses includes two symmetrical lenses 810a, 810b (e.g., lenses having the same focal length) such that the maximum angle of incidence of the light beam received by lens 810a from connector 410 is the same as the maximum angle of the light beam emitted from lens 810b. The maximum angle of attack (i.e., the maximum angle of light energy incident on sensor 376) is Fig. 8AThe inventors have recognized and appreciated that reducing the maximum angle of attack α can increase the contrast of the signal redirected by Fizeau 374 to sensor 376. In some embodiments described herein, by amplifying the optical signal transmitted through lens 372, the maximum angle of attack α of the optical energy output from lens 372 can be reduced.

[0052] Without modifying the arrangement and / or orientation of the optical fibers within the connector 410, the acceptance angle of the light beam output from the connector 410 and received by the lens 372 can be substantially fixed. Some conventional solutions for reducing the acceptance angle include some of the patterns that bend the optical fiber to cut off the optical signal. However, such techniques also reduce the total energy in the signal, which may be undesirable for some applications where the amount of energy in the optical signal may be small. Rather than reducing the energy in the optical energy provided as input to the lens 372, some embodiments disclosed herein reduce the maximum angle of attack α by using a lens 372 that amplifies the optical signal passing through the lens 372 (e.g., by selecting a lens or combination of lenses with appropriate focal length characteristics). For single-channel optical devices in which a single line is to be generated on the sensor 376 (and therefore crosstalk between lines on the sensor 376 need not be considered), the lens 372 can be configured using a single lens that provides amplification of the optical signal received from the connector 410. In a multi-channel optical device in which multiple lines are to be produced on sensor 376 (and therefore in which crosstalk between lines on sensor 376 may be important for distinguishing multiple interference pattern signals), examples of which are described herein, lens 372 can be configured using multiple lenses that collectively provide amplification of the incident optical signal.

[0053] Figure 8B Schematically illustrates a detector module including a lens 372 configured to perform amplification of an optical signal received from a connector 410 according to some embodiments. Figure 8B , lens 372 may be implemented as a set of asymmetric lenses 810b, 810c having different focal lengths. The set of lenses 810b, 810c may collectively provide amplification of an optical signal received from connector 410, which in turn provides an optical signal at the output of lens 810b having a relative focal length. Fig. 8A 810a, 810b (i.e., β < α). For example, if the focal length of lens 810b is selected to be 7.8 and the focal length of lens 810c is selected to be 5.5, then the magnification factor of lens 372 will be 7.8 / 5.5 = 1.4. By reducing the maximum angle of attack β, the contrast (e.g., peak-to-peak amplitude / average amplitude) of the interferometer signal is improved relative to when a larger maximum angle of attack α is used.

[0054] Although configuring lens 372 to have a higher magnification reduces the maximum angle of attack β, thereby improving the contrast of the signal, configuring lens 372 to provide too much magnification may have some undesirable consequences regarding the signal captured by sensor 376 . Fig. 7A Schematic diagram illustrating a representation of a signal generated by a two-dimensional image sensor (e.g., Figure 3 376) captured by the image sensor 376 shown in FIG. 3, in some embodiments, the detector module includes a device configured as shown in FIG. Fig. 8A Lens 372 is a pair of symmetric lenses shown in FIG. Fig. 8A An image 820 of a two-dimensional image sensor is schematically illustrated in which two lines corresponding to the interferogram signals for two channels of the multi-channel optical pressure sensor are separated by a distance d1 . Figure 8B Schematically illustrates an image 830 of a two-dimensional image sensor in which two lines corresponding to interference pattern signals for two channels of a multi-channel optical pressure sensor that have been amplified using lenses 810b, 810c are separated by a distance d2. As can be observed by comparing images 820 and 830, compared to using Fig. 8A The lens design shown in Figure 8B The amplification of the optical signal of the lens design results in a greater number of pixels used to represent each of the interferogram signals on the sensor 376. By using additional pixels to represent the amplified interferogram signals, the processing resources required to process the captured signals (e.g., using Figure 3 376) can be increased relative to the larger magnification of the embodiment in which a smaller magnification is used. In addition, the distance between the two interferogram signals can also be amplified (i.e., d2>d1), which can limit the number of additional channels of information that can be captured by the sensor 376 without increasing the size of the sensor. As should be appreciated, the selection of the best components for the lens 372 that increase the magnification to improve the contrast of the interferogram signals while reducing the spread of the detected signal on the sensor 376 can be determined based on the specific application and / or Fizeau design.

[0055] The inventors have recognized that configuring lens 372 to have a relatively small magnification (e.g., 1.2x, 1.3x, 1.4x, 1.5x) can provide sufficient magnification to improve contrast while controlling the pixel spread of the interferogram signal on sensor 376. For example, for some applications including a multi-channel optical pressure sensor as described herein, by selecting a suitable magnification factor for lens 372, the pixel spread of the interferogram signal captured by sensor 376 can be controlled within reasonable limits. In some embodiments, the magnification factor of lens 372 can be greater than 1.1, greater than 1.2, greater than 1.3, greater than 1.4, or greater than 1.5. In some embodiments, the magnification factor of lens 372 can be less than 3, less than 2.5, less than 2, less than 1.5, less than 1.4, less than 1.3, or less than 1.2. In some embodiments, the magnification factor can be within any of the foregoing ranges. For example, the magnification factor can be greater than 1.1 and less than 2, greater than 1.1 and less than 1.5, greater than 1.2 and less than 1.4, and so on.

[0056] Having thus described several aspects and embodiments of the present technology set forth in the present disclosure, it should be understood that various changes, modifications and improvements are readily apparent to those skilled in the art. The changes, modifications and improvements are intended to be within the spirit and scope of the technology described herein. For example, a person skilled in the art will easily envision a variety of other components and / or structures for performing the functions described herein and / or obtaining one or more of the results and / or advantages described herein, and each of these variations and / or modifications is considered to be within the scope of the embodiments described herein. A person skilled in the art can recognize or be able to determine many equivalents of the specific embodiments described herein using only routine experiments. Therefore, it should be understood that the aforementioned embodiments are presented only by way of example and within the scope of the appended claims and their equivalents, inventive embodiments may be practiced differently from the specific description. In addition, if features, systems, objects, materials, kits and / or methods are not mutually contradictory, any combination of two or more of the features, systems, objects, materials, kits and / or methods is included within the scope of the present disclosure.

[0057] The embodiments described above can be implemented in any of numerous ways. One or more aspects and embodiments of the performance of the process or method disclosed herein can utilize program instructions that can be executed by a device (e.g., a computer, a processor or other device) to execute or control the performance of the process or method. In this regard, various inventive concepts can be embodied as computer-readable storage media (or multiple computer-readable storage media) (e.g., computer memory, one or more floppy disks, optical disks, optical disks, tapes, flash memories, circuit configurations in field programmable gate arrays or other semiconductor devices or other tangible computer storage media) encoded with one or more programs that execute one or more methods of the various embodiments described above when executed on one or more computers or other processors. One or more computer-readable media can be transportable so that the one or more programs stored above can be loaded onto one or more different computers or other processors to implement various aspects of the aspects described above. In some embodiments, the computer-readable medium can be a non-transitory medium.

[0058] The above-described embodiments of the present technology can be implemented in any of numerous ways. For example, the embodiments can be implemented using hardware, software, or a combination thereof. When implemented in software, the software program code can be executed on any suitable processor or set of processors, whether provided in a single computer or distributed among multiple computers. It should be understood that any component or set of components that perform the functions described above can be generally regarded as a controller that controls the functions described above. The controller can be implemented in numerous ways, such as using dedicated hardware, or using general-purpose hardware (e.g., one or more processors) that is programmed using microprogram code or software to perform the functions cited above, and can be implemented in a combination of several ways when the controller corresponds to multiple components of the system.

[0059] Moreover, it should be appreciated that a computer may be embodied in any of a number of forms, such as, by way of non-limiting example, a rack-mounted computer, a desktop computer, a laptop computer, or a tablet computer. Additionally, a computer may be embedded in a device not generally regarded as a computer but with suitable processing capabilities, including a personal digital assistant (PDA), a smart phone, or any other suitable portable or fixed electronic device.

[0060] In addition, a computer may have one or more input and output devices. Among other things, these devices may be used to present a user interface. Examples of output devices that can be used to provide a user interface include a printer or display screen for visual output presentation and a speaker or other sound generating device for audible output presentation. Examples of input devices that can be used for a user interface include a keyboard and a pointing device, such as a mouse, a touch pad, and a digitizing tablet. As another example, a computer may receive input information through speech recognition or in other audible formats.

[0061] Such computers may be interconnected in any suitable form by one or more networks, including local or wide area networks, such as enterprise networks and intelligent networks (IN) or the Internet. Such networks may be based on any suitable technology and may operate according to any suitable protocol, and may include wireless networks, wired networks, or fiber optic networks.

[0062] In addition, as described, some aspects may be embodied as one or more methods. The actions performed as part of a method may be ordered in any suitable manner. Thus, embodiments may be constructed in which the actions are performed in an order different from that illustrated, which may include performing some actions simultaneously, even though they are shown as sequential actions in an illustrative embodiment.

[0063] All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.

[0064] Unless clearly indicated to the contrary, the indefinite articles "a and an" as used herein in the specification and claims should be understood to mean "at least one."

[0065] As used herein in the specification and claims, the phrase "and / or" should be understood to mean "either or both" of the elements so combined, i.e., elements that exist in combination in some cases and in separation in other cases. Multiple elements listed with "and / or" should be understood in the same manner, i.e., "one or more" of the elements so combined. In addition to the elements specifically identified by the "and / or" clause, other elements may optionally be present, whether related or unrelated to those specifically identified. Thus, as a non-limiting example, when used in conjunction with open language such as "including", a reference to "A and / or B" in one embodiment may refer to only A (optionally including elements other than B); in another embodiment, to only B (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); and so on.

[0066] As used herein in the specification and in the claims, the phrase "at least one" referring to a list of one or more elements should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each element specifically listed in the list of elements, and not excluding any combination of the elements in the list of elements. This definition also allows that elements other than the elements specifically identified in the list of elements to which the phrase "at least one" refers may optionally be present, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, in one embodiment, "at least one of A and B" (or equivalently, "at least one of A or B", or equivalently, "at least one of A and / or B") may refer to at least one (optionally including more than one) A, without B (and optionally including elements other than B); in another embodiment, to at least one (optionally including more than one) B, without A (and optionally including elements other than A); in yet another embodiment, to at least one (optionally including more than one) A and at least one (optionally including more than one) B (and optionally including other elements); and so on.

[0067] In addition, the words and terms used herein are for illustrative purposes and should not be considered limiting. The use of "including," "comprising," or "having," "containing," "involving," and variations thereof herein is intended to encompass the items listed thereafter and their equivalents as well as additional items.

[0068] In the claims and in the above description, all transitional phrases (e.g., "includes," "comprising," "carrying," "having," "containing," "involving," "holding," "consisting of," etc.) should be understood as open-ended, i.e., meaning including but not limited to. The transitional phrases "consisting of" and "consisting essentially of" should be closed or semi-closed transitional phrases, respectively.

[0069] The use of ordinal terms such as "first", "second", "third", etc. in the claims to modify claim elements does not itself mean that the claim elements have any priority, precedence or order over another claim element, nor does it mean the temporal order in which the actions of the method are performed, but is merely used as a label to distinguish the claim element with a specific name from another element with the same name (except for the use of ordinal terms) to distinguish the claim element.

Claims

1. A multi-channel optical pressure sensor, comprising: at least one light emitting diode (LED); a plurality of sensors including a first sensor coupled to the at least one LED via at least one first optical fiber and a second sensor coupled to the at least one LED via at least one second optical fiber; a detector module coupled to the first sensor and the second sensor, the detector module comprising: at least one lens; and an image sensor configured to sense light received from the at least one lens; and At least one hardware processor configured to determine a first pressure measured at the first sensor and a second pressure measured at the second sensor based at least in part on the light sensed by the image sensor.

2. The sensor of claim 1, wherein the at least one LED comprises: a first LED configured to generate a first light having a first spectrum; and A second LED is configured to generate a second light having a second spectrum. 3 . The sensor according to claim 2 , wherein the first spectrum has a peak wavelength in the range of 550 nm to 670 nm, and the second spectrum has a peak wavelength in the range of 800 nm to 900 nm. The sensor according to claim 3 , wherein the first spectrum has a peak wavelength in the range of 550 nm to 600 nm. The sensor according to claim 2 , wherein a peak wavelength of the first spectrum is 4 / 5 of a peak wavelength of the second spectrum. The sensor according to claim 2 , wherein the first LED and / or the second LED are smaller than 1 mm.

7. The sensor of claim 2, wherein the first LED and / or the second LED are phosphor-converted LEDs.

8. The sensor of claim 1, wherein the at least one LED comprises a single LED having a broad spectrum.

9. The sensor according to claim 2, further comprising: a first optical element disposed between the at least one LED and the plurality of sensors, the first optical element being configured to: receiving the first light and the second light; and A third light and a fourth light are output, each of the third light and the fourth light having a third spectrum.

10. The sensor according to claim 9, further comprising: a second optical element coupled to the first optical element, the first sensor, and the detector module; and A third optical element is coupled to the first optical element, the second sensor, and the detector module.

11. The sensor according to claim 10, wherein: The second optical element is configured to provide first reflected light from the first sensor to the detector module, and The third optical element is configured to provide second reflected light from the second sensor to the detector module.

12. The sensor of claim 1, wherein the at least one lens comprises a planar lens.

13. The sensor of claim 12, wherein the planar lens comprises a set of D-shaped lenses having curved edges facing each other.

14. The sensor of claim 12, wherein the at least one lens is configured to reduce spherical aberration in the light received from the first sensor and the second sensor.

15. The sensor of claim 1, wherein the at least one lens is configured to amplify a light signal incident on the at least one lens.

16. The sensor of claim 15, wherein a magnification factor of the at least one lens is at least 1.1 and less than 3.

17. The sensor of claim 16, wherein the amplification factor is less than 1.

5.

18. The sensor of claim 17, wherein the amplification factor is less than 1.

3.

19. The sensor of claim 15, wherein the at least one lens comprises at least two lenses that collectively amplify the optical signal incident on the at least one lens.

20. The sensor of claim 19, wherein the at least two lenses include a first lens having a first focal length and a second lens having a second focal length different from the first focal length.

21. The sensor according to claim 20, wherein Each of the first lens and the second lens is a D-shaped lens having a curved edge, and the curved edges of the first lens and the second lens are arranged to face each other.

22. The sensor of claim 1, wherein the detector module further comprises a Fizeau disposed between the at least one lens and the image sensor.

23. The sensor of claim 22, wherein the image sensor comprises a two-dimensional image sensor.

24. The sensor of claim 23, wherein the at least one lens and the Fizeau are configured to jointly project the light received from the first sensor and the second sensor as two lines onto the two-dimensional image sensor.

25. The sensor of claim 24, wherein the two lines are two parallel lines.

26. A sensor according to claim 24, wherein each of the two lines on the two-dimensional image sensor includes an interference pattern, and wherein determining a first pressure measured at the first sensor and a second pressure measured at the second sensor based at least in part on the light sensed by the image sensor includes determining the first pressure and the second pressure based on corresponding interference patterns.

27. A circulating support device comprising: Rotor; a motor configured to drive the rotor to rotate at one or more speeds; a first optical pressure sensor configured to detect a first pressure signal; a second optical pressure sensor configured to detect a second pressure signal; and At least one hardware processor configured to: A differential pressure signal is determined based at least in part on the first pressure signal and the second pressure signal.

28. The cyclic support device of claim 27, wherein the at least one hardware processor is further configured to determine a flow rate through the cyclic support device based at least in part on the differential pressure signal.

29. The cyclic support device according to claim 27, further comprising: a first light emitting diode (LED) coupled to the first optical pressure sensor and the second optical pressure sensor, the first LED configured to generate a first light having a first spectrum; and A second LED is coupled to the first optical pressure sensor and the second optical pressure sensor, the second LED being configured to generate a second light having a second spectrum.

30. The loop support device of claim 29, wherein the first spectrum has a peak wavelength in the range of 550 nm to 670 nm, and the second spectrum has a peak wavelength in the range of 800 nm to 900 nm.

31. The loop support device of claim 30, wherein the first spectrum has a peak wavelength in the range of 550 nm to 600 nm.

32. The loop support device of claim 29, wherein the peak wavelength of the first spectrum is 4 / 5 of the peak wavelength of the second spectrum.

33. The cyclic support device of claim 29, wherein the first LED and / or the second LED are smaller than 1 mm.

34. The looping support device of claim 29, wherein the first LED and / or the second LED are phosphor-converted LEDs.

35. The cyclic support device of claim 29, further comprising: A first optical element arranged to: receiving the first light and the second light; and A third light and a fourth light are output, each of the third lights having a third spectrum, the third light is provided to the first optical pressure sensor, and the fourth light is provided to the second optical pressure sensor.

36. The cyclic support device of claim 35, further comprising: a second optical element coupled to the first optical element and the first optical pressure sensor; and A third optical element is coupled to the first optical element and the second optical pressure sensor.

37. The cyclic support apparatus of claim 36, further comprising a detector module, wherein: The second optical element is configured to provide first reflected light from the first optical pressure sensor to the detector module, and The third optical element is configured to provide second reflected light from the second optical pressure sensor to the detector module.

38. The cyclic support device of claim 29, further comprising: a detector module coupled to the first optical pressure sensor and the second optical pressure sensor, the detector module comprising: at least one lens; and An image sensor is configured to sense light received from the at least one lens.

39. The cyclic support device of claim 38, wherein the at least one lens comprises a planar lens.

40. The cyclic support device of claim 39, wherein the planar lenses comprise a set of D-shaped lenses having curved edges facing each other.

41. The cyclic support apparatus of claim 38, wherein the at least one lens is configured to reduce spherical aberration in the light received from the first optical pressure sensor and the second optical pressure sensor.

42. The cyclic support device of claim 27, wherein the at least one lens is configured to amplify an optical signal incident on the at least one lens.

43. The cyclic support device of claim 42, wherein the magnification factor of the at least one lens is at least 1.1 and less than 3.

44. The cyclic support device of claim 43, wherein the amplification factor is less than 1.

5.

45. The cyclic support device of claim 44, wherein the amplification factor is less than 1.

3.

46. ​​The cyclic support device of claim 42, wherein the at least one lens comprises at least two lenses that collectively amplify the optical signal incident on the at least one lens.

47. The cyclic support device of claim 46, wherein the at least two lenses include a first lens having a first focal length and a second lens having a second focal length different from the first focal length.

48. The cyclic support device of claim 47, wherein Each of the first lens and the second lens is a D-shaped lens having a curved edge, and the curved edges of the first lens and the second lens are arranged to face each other.

49. The cyclic support apparatus of claim 27, wherein the detector module further comprises a Fizeau disposed between the at least one lens and the image sensor.

50. The cyclic support apparatus of claim 38, wherein the detector module further comprises a Fizeau disposed between the at least one lens and the image sensor.

51. The looping support apparatus of claim 50, wherein the image sensor comprises a two-dimensional image sensor.

52. The cyclic support apparatus of claim 51, wherein the at least one lens and the Fizeau are configured to collectively project the light received from the first optical pressure sensor and the second optical pressure sensor as two lines onto the two-dimensional image sensor.

53. The endless support device of claim 52, wherein the two lines are two parallel lines.

54. The cyclic support device of claim 52, wherein: each of the two lines on the two-dimensional image sensor comprises an interference pattern, The at least one hardware processor is further configured to: determine a first pressure measured at the first optical pressure sensor and a second pressure measured at the second optical pressure sensor based at least in part on light sensed by the image sensor by determining the first pressure and the second pressure based on corresponding interference patterns, and Determining the differential pressure signal based at least in part on the first pressure signal and the second pressure signal includes determining the differential pressure signal based on the first pressure and the second pressure.

Images