COMPACT FLUORESCENCE ENDOSCOPY VIDEO SYSTEM
A fluorescence endoscopy video system includes a multimode light source that produces light for color and fluorescence imaging modes. Light from the light source is transmitted through an endoscope to the tissue under observation. The system also includes a compact camera for color and fluorescence imaging. Images obtained through the endoscope are optically divided and projected onto one or more image sensors by a fixed beam splitter in the camera. The fixed beam splitter eliminates the need for inserting a movable mirror into the light path between the endoscope and the image sensors. Image signals from the camera are processed in the system processor/controller where a contrast enhancement function can be applied. The contrast enhancement function increases the color contrast between normal tissue and tissue suspicious for early cancer. Finally, the system also includes a calibration feature whereby the system performance can be maintained when used with different endoscopes.
1 . A fluorescence endoscopy video system including:
a multimode light source for producing white light, fluorescence excitation light or fluorescence excitation light with a reference reflectance light;
an endoscope for directing the light from the light source into a patient to illuminate a tissue sample and to collect the reflected light or fluorescence light emitted from the tissue;
a camera positioned to receive the light collected by the endoscope, the camera including:
a color image sensor having integrated color filters;
a low light image sensor;
a beam splitter for splitting the light received from the endoscope into at least two beams and directing a first of the at least two beams onto the color image sensor;
a dichroic splitter and filter assembly that receives a second of the at least two beams from the beam splitter and divides the second into two spectral components and projects the two spectral components onto separate imaging areas disposed in the same image plane of the low light image sensor,
one or more additional filters positioned in front of the low light and color image sensors for selectively transmitting light of desired wavelengths;
one or more optical imaging components that project images onto both the color image sensor and the low light image sensor;
an image processor/controller for digitizing, processing and encoding the image signals received from the sensor(s) as a video signal; and
a video monitor for displaying the video signals.
2 . The system of claim 1 , wherein the camera is attached to the portion of the endoscope that remains outside of the body.
3 . The system of claim 1 , wherein the camera is built into the insertion portion of the endoscope.
4 . The system of claim 1 , wherein the dichroic splitter and filter assembly splits the light into green and red bands while blocking out-of-band light to the extent that the light received by the sensors is substantially composed of light of green or red wavelengths and minimally composed of light of out-of-band wavelengths.
5 . The system of claim 1 , wherein the dichroic splitter and filter assembly splits the light into blue and red bands while blocking out-of-band light to the extent that the light received by the sensors is substantially composed of light of blue and red wavelengths and minimally composed of light of out-of-band wavelengths.
6 . The system of claim 1 , wherein the dichroic splitter and filter assembly splits the light into red and near-infrared bands while blocking out-of-band light to the extent that the light received by the sensors is substantially composed of light of red and near-infrared wavelengths and minimally composed of light of out-of-band wavelengths.
7 . The system of claim 1 , wherein the dichroic splitter and filter assembly splits the light into green and near-infrared bands while blocking out-of-band light to the extent that the light received by the sensors is substantially composed of light of green and near-infrared wavelengths and minimally composed of light of out-of-band wavelengths.