Methods and means for multispectral imaging

An imaging apparatus for acquisition of fluorescence and reflectance images of an object comprising

• at least a first light source providing a first light having at least two spectral regions of high intensity and at least a second light source providing a second light having at least one spectral region of high intensity, wherein the first light has at least regions of low intensity that are of longer wavelengths to a region of high intensity,
• wherein the ratio of the light intensity between regions of high intensity at shorter wavelength and regions of low light intensity of longer wavelength for the first light is ≥1×102,
• wherein the at least one first light source and the at least one second light source are configured to alternatingly illuminate the object with the first light and the second light,
• a sensor array arranged for recording a first image of the object during illumination of the object with the first light and a second image of the object during illumination of the object with the second light,
• wherein the sensor array is a multichannel array where each channel has a distinct spectral sensitivity, and
• an attenuator,
• wherein the attenuator comprises a multiple bandpass filter positioned between the object and the sensor array and having transmission characteristics, which are complementary to the first light, so as to attenuate the light recorded by the sensor array in at least said two spectral regions in which the first light has high intensities, and
• wherein at least one of
• (a) the attenuation ratio between the intensity of the unattenuated to the attenuated spectral regions is ≥1×102, and
• (b) the amount of attenuation of the light recorded by the sensor array in at least one of the spectral regions in which the first light has high intensities is such that the intensity of the light recorded in unattenuated spectral regions is higher than the intensity of the light recorded in the sum of the attenuated spectral regions.