Automatic alignment of a contrast enhancement system
An apparatus and method for insuring the proper alignment of a detected vein pattern and a projected vein pattern are disclosed. The apparatus enhances the visual appearance of veins so that an error that can lead to improper patient care or injury can be avoided.
1. An vein imaging and alignment system, for use in vein imaging to ensure the proper alignment of a detected vein pattern and a visible projection of the vein pattern, said imaging alignment system comprising:
means for illuminating a field of view with a first wavelength of infrared light, to create an image contrast formed by differential amounts of absorption and reflection by the veins of the vein pattern and the surrounding tissue therein;
an alignment card positioned in the field of view, said alignment card comprising a material formed into a pattern, said material configured to emit a second wavelength of light when exposed to a visible light at a third wavelength;
a camera configured to capture said image contrast of said reflected first wavelength of infrared light from the field of view; and
a projector, said projector configured to project said captured image contrast onto the field of view using said visible light at said third wavelength; said camera configured to capture said second wavelength of light emitted by said pattern of material, and to capture said visible light at said third wavelength reflected from said pattern of material, said camera further configured to distinguish said wavelength of visible light at said third wavelength reflected by said pattern of material, from said second wavelength of light emitted by said pattern of material; said projector comprising means for image processing configured to utilize said distinction between said reflection of said projected alignment card pattern at said third wavelength of light captured by said camera, and said second wavelength of emitted light from said alignment card pattern also captured by said camera, to align said projected image with said reflected image contrast at said first wavelength of infrared light.
2. The system according to claim 1 wherein said material of said alignment card pattern comprises a fluorescent material.
3. The system according to claim 1 wherein said alignment card pattern comprises a known pattern.
4. The system according to claim 1 wherein said third wavelength of light comprises a green wavelength of light.
5. The system according to claim 4 wherein said projector is configured to project said green light to fill the area in the field of view outside of the veins of the vein pattern, up to the edges of the veins.
6. The system according to claim 1 wherein said second wavelength of light comprises a red wavelength.
7. A vein contrast enhancer, for use in vein imaging and for ensuring the proper alignment of a vein pattern, detected as an image contrast reflected from a field of view, and a projection of the image contrast onto the field of view, said vein contrast enhancer comprising:
a light source configured to emit a first wavelength of infrared light onto the field of view, to create an image contrast formed by differential absorption and reflection of said first wavelength of infrared light by the veins of the vein pattern and the surrounding tissue therein;
an alignment card positioned within the field of view and comprising a material formed into a pattern, said material configured to emit a second wavelength of light when exposed to a visible light at a third wavelength;
a camera, said camera configured to capture said image contrast of said reflected first wavelength of infrared light from the field of view;
a projector, said projector configured to project said captured image contrast onto the field of view using said visible light at said third wavelength, said camera configured to capture said second wavelength of light emitted by said pattern of material, and to capture said visible light at said third wavelength reflected from said pattern of material, said camera further configured to distinguish said wavelength of visible light at said third wavelength reflected by said pattern of material, from said second wavelength of light emitted by said pattern of material; and wherein said projector is configured to perform image processing, with said projector configured to utilize said distinction between said reflection of said projected alignment card pattern at said third wavelength of light captured by said camera, and said second wavelength of emitted light from said alignment card pattern also captured by said camera, to align said projected image with said reflected image contrast.
8. The vein contrast enhancer according to claim 7 wherein said material of said alignment card pattern comprises a fluorescent material.
9. The vein contrast enhancer according to claim 8 wherein said alignment card pattern comprises a known pattern.
10. The vein contrast enhancer according to claim 9 wherein said one or more selective wavelengths of visible light comprises a green wavelength of light.
11. The vein contrast enhancer according to claim 10 wherein said projector is configured to project said green light to fill in the field of view outside of the veins of the vein pattern, up to the edges of the veins.
12. The vein contrast enhancer according to claim 11 wherein said second wavelength of light comprises a red wavelength of light.
13. The vein contrast enhancer according to claim 12 wherein said source of infrared light is a light source from the group of light sources consisting of a laser; and a light emitting diode (LED).