Method and apparatus using a medical imaging head for fluorescent imaging

A method for detecting visible and infrared light using a medical imaging system, said medical imaging system comprising a dichroic prism assembly and a camera module configured to receive visible light and infrared light from an object image, the method comprising:

• exciting a fluorescence agent in a tissue sample with excitation light;
• illuminating the tissue sample with visible light;
• receiving light from the object image through an entrance face of the dichroic prism assembly, said light comprising visible light and one or more infrared fluorescence light originating from the fluorescence agent;
• splitting the received light into a first, second, and third optical path;
• filtering the received light in the first, second, and third optical path through a first, second and third optical filter, respectively;
• detecting the filtered light in the first, second, and third optical path with a first, second and third sensor, respectively wherein the first, second, and third filters, in any order, are a green filter, an infrared filter, and a red/blue patterned filter comprising red and blue filters in alternating pattern so that half of the light received by the red/blue patterned filter goes through a blue filter and half of the light received by the red/blue patterned filter goes through a red filter,
• wherein the dichroic prism assembly comprises at least a first, second, and third prism, each prism having a respective first, second, and third exit face,
• wherein:
• the first exit face is provided with the first sensor,
• the second exit face is provided with the second sensor, and
• the third exit face is provided with the third sensor, and
• wherein the dichroic prism assembly comprises a fourth prism, said fourth prism having a cross section with at least five corners, each corner having an inside angle of at least 90 degrees, the fourth prism providing a fourth optical path with a fourth filter and having a fourth exit face provided with a fourth light sensor, wherein the fourth filter is a second infrared filter.