Biomedical Imaging Using a Barcode Scanner

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Biomedical Imaging Using a Barcode Scanner

By: Nidhi Khurana Rajesh SatpathyR: Hi, my name is Rajesh Satpathy.N: And my name is Nidhi Khurana. Today, well be presenting our project, titled Biomedical imaging using a barcode scanner.

1Challenge in biomedical imaging Picture of current biomedical imaging system

Challenge: Can we build a low cost biomedical imaging system?

Wojtkowski, M., Applied Optics 49, D30-D61, 2010.R: We can potentially reduce the costs associated with biomedical imaging, by using a barcode scanner. Our project suggests that we can lower the pricing of imaging by as much as 60x, making it not only affordable for hospitals to buy, but an affordable procedure for an average patient.

What challenges are in current systems

Medical problems, other uses of current systemsDevices usedCost of such devices

Picture of example- for exampleIMPORTANT we want to look UNDER the surfaceIn particular we are shooting for a system that is cheaper than the current one

2Challenge in biomedical imaging Picture of current biomedical imaging system

Challenge: Can we build a low cost biomedical imaging system?

Wojtkowski, M., Applied Optics 49, D30-D61, 2010.

R: We can potentially reduce the costs associated with biomedical imaging, by using a barcode scanner. Our project suggests that we can lower the pricing of imaging by as much as 60x, making it not only affordable for hospitals to buy, but an affordable procedure for an average patient.

What challenges are in current systems

Medical problems, other uses of current systemsDevices usedCost of such devices

Picture of example- for exampleIMPORTANT we want to look UNDER the surfaceIn particular we are shooting for a system that is cheaper than the current one

3Challenge in biomedical imaging Picture of current biomedical imaging system

Challenge: Can we build a low cost biomedical imaging system?Use a barcode scanner

Wojtkowski, M., Applied Optics 49, D30-D61, 2010.

R: We can potentially reduce the costs associated with biomedical imaging, by using a barcode scanner. Our project suggests that we can lower the pricing of imaging by as much as 60x, making it not only affordable for hospitals to buy, but an affordable procedure for an average patient.

What challenges are in current systems

Medical problems, other uses of current systemsDevices usedCost of such devices

Picture of example- for exampleIMPORTANT we want to look UNDER the surfaceIn particular we are shooting for a system that is cheaper than the current one

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N: Lets take a picture of a subject, like a strawberry.

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We need light and camera to take a picture.

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Near infrared lightN: But we want to take a picture of the inside parts of the strawberryR: So we need an infrared light because it penetrates the surface of the subject and reflects back its side to our camera that reads infrared light.

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Depth scanninghttp://cdn.wn.com/pd/dc/9d/cfc0915c804ff4dbb70ccee3feed_grande.jpgCross sectionsN: So in this image, the sphere and the half sphere can be like the surface of the strawberry, the cylinder and the cone represent the inside. Bio imaging allows us to see the outside and the inside laid on top of each other as seen in but it also uses this concept of depth scanning that allows us to go past the surface and see the interior when we see only the cylinder or cone. We need to use interferometry to reject unwanted light and get signals inside object.

Rather than taking a mere picture of a subject we wanted to see certain sections at certain depths. (cross sections of the sample)8Optical Coherence Tomography (OCT)

GalvonometerN: Depth scanning and in vivo imaging are part of a type of biomedical imaging called OCT imaging, or optical coherence tomography. What this does is create an image noninvasively similar to the methods used by ultrasounds. In this case an optical beam is pointed at a sample and some of that light is reflected from the interior of that sample. Although not all of the light is reflected back, enough comes back to the sensor, in our case a bar code scanner, that an image can be acquired.

Rejecting background noise is possible with interferograms through a comparison with the reference lasers input and the input from the sample. The interference from the reference will drown out the

Talk about dynamic range9

Barcode ScannerWe believe that a Barcode scanner can be used as the sensor in OCT technology. Many of you are familiar with a bar code scanner like this. Grocery stores are a common place where you see them.10

Barcode ScannerThis is how the bar code scanner works. The light source sends light through a lens which focuses the light onto the barcode and then light is reflected off of the barcode through another lens which focuses the reflected light onto the barcode scanner. In our case the barcode is the strawberry or the sample11

Barcode Scanner2 rows of 640 photon receptors (sensors)SensorsAligned linearly Measure the light intensityInformation sent to a processing systemLight intensity translates into an imageR: Talk about barcode scanner picture: 2 rows of 640 of photon receptors (sensors)-Sensors Aligned linearly Measure the light intensity Information sent to a processing system Light intensity translates into an image translates light intensity to an image

2 rows of 640 of photon receptors (sensors)SensorsAligned linearly Measure the light intensityInformation sent to a processing system

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Barcode Scanner Versus CCD CameraThe barcode scanners pixel is about 60 micrometers squared large as compared to CCD pixels, which are only about 10 micrometers. The advantage of a bar code scanner is that almost all the light intensity from the beam is covered by the detection pixel. In a CCD camera, most of the light intensity (80%) is lost. The bar code scanner is therefore much more efficient.

Laser point to the spot on the graph that is ours and the point on the graph at which modern cameras operate at.13

Barcode Scanner Versus CCD CameraRatio of pixel size to amount of total light received by the pixelPixel size (m)Barcode scannerCCDThe barcode scanners pixel is about 60 micrometers squared large as compared to CCD pixels, which are only about 10 micrometers. The advantage of a bar code scanner is that almost all the light intensity from the beam is covered by the detection pixel. In a CCD camera, most of the light intensity (80%) is lost. The bar code scanner is therefore much more efficient.

Laser point to the spot on the graph that is ours and the point on the graph at which modern cameras operate at.14

Specified pixel separation and focal length affecting image resolutionThe new box, located in the center of the slide, represents the resolution that our technology can acquire. It obviously isnt at the same high resolution that modern technology is at, but theres a reason for that, outside of simply lowering the price tag.

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Specified pixel separation and focal length affecting image resolutionThe new box, located in the center of the slide, represents the resolution that our technology can acquire. It obviously isnt at the same high resolution that modern technology is at, but theres a reason for that, outside of simply lowering the price tag.

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Specified pixel separation and focal length affecting image resolutionThe new box, located in the center of the slide, represents the resolution that our technology can acquire. It obviously isnt at the same high resolution that modern technology is at, but theres a reason for that, outside of simply lowering the price tag.

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Specified pixel separation and focal length affecting image resolutionThe new box, located in the center of the slide, represents the resolution that our technology can acquire. It obviously isnt at the same high resolution that modern technology is at, but theres a reason for that, outside of simply lowering the price tag.

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Experimental SetupSpectrometerBarcode ScannerSLED Most important part of the system as it is the source of the broadband near-infrared light this penetrates the subject and is then reflected back out.HE-NE Visible laser that is collimated with the SLED in order to calibrate the system.IS This is the optical isolator which focuses the laser into a Gaussian pattern of distribution this focuses the disparate and random beams of the laser into a circle, minimalizing loss of data.PBS The polarization beam splitter reflects different intensities of light in different ways. When the laser is focused and is coming from the direction of the source, the PBS allows it straight through towards the fiber coupler. If it coming back from the subjects side at an intensity of 10%, itll be directed towards the spectrometer. 90/10 Fiber Coupler The fiber coupler splits the light into two beams, one of which is 90% intensity and the other of which is 10%. The 90% beam is sent towards the scan mirrors, where it will be directed to the sample. The 10% is sent towards the reference, a fixed mirror which simply returns the light to aid in the clarification of the subject image by eliminating background noise. When these two beams are reflected back, they should be at about the same intensity. The 90% beam is reduced by about 9 times because the opaque sample is not reflective enough to return the full intensity of the beam. This ends up creating beams of equivalent intensities.Scan Mirrors Two mirrors, one of which moves in the X direction while the other moves in the Y direction. When used in combination with each other, the mirrors allo