A spectrometer comprising: a diffuser configured to diffuse light impinging thereon; a filter matrix arranged to receive the diffuse light and to angularly encode a spectrum of the light passing through the filters of the filter matrix; a lens array to spatially Fourier-transform the angularly-encoded light into a spatially-encoded spectrum; an aperture array comprising a plurality of apertures between the filter matrix and the lens array, wherein the plurality of apertures of the aperture array are configured to define a lens aperture for each lens of the lens array, each lens aperture being limited to one of the filters of the filter matrix; an image detector comprising multiple sensor regions arranged to detect the spatially-encoded spectrum, a wavelength of light at a given sensor region can be determined based on a location of the given sensor region relative to an optical axis of the lens array; a support array comprising a plurality of support structures, the support array being configured to support the lens array and fix a distance from the lens array to the light detector, the support array comprising a plurality of channels through which the spatially-encoded spectrum passes, the plurality of channels being defined with the plurality of support structures, wherein the diffuser, the filter matrix, and the lens array, the support array, and the detector form a light path, the light path passing sequentially through the diffuser, the filter matrix, the lens array, the support array, and ending at the light detector; wherein the light path from the diffuser to the detector is less than 9mm, wherein the resolution of the spectrometer is less than 10nm, wherein the filter matrix comprises interference filters, wherein the light path comprises a plurality of isolated optical paths extending from the filter matrix through the lens array to the multiple sensor regions, wherein each isolated optical path of the plurality of isolated optical paths is established from a single filter of the filter matrix to a single aperture of the aperture array to a single lens of the lens array to a single channel of the support array to a sensor region of the image detector, and wherein the plurality of isolated optical paths is established at least in part by the plurality of apertures of the aperture array being formed in a non-optically transmissive material thereby to prevent cross talk between the filters of the filter matrix. a diffuser configured to diffuse light impinging thereon; a filter matrix arranged to receive the diffuse light and to angularly encode a spectrum of the light passing through the filters of the filter matrix; a lens array to spatially Fourier-transform the angularly-encoded light into a spatially-encoded spectrum; an aperture array comprising a plurality of apertures between the filter matrix and the lens array, wherein the plurality of apertures of the aperture array are configured to define a lens aperture for each lens of the lens array, each lens aperture being limited to one of the filters of the filter matrix; an image detector comprising multiple sensor regions arranged to detect the spatially-encoded spectrum, a wavelength of light at a given sensor region can be determined based on a location of the given sensor region relative to an optical axis of the lens array; a support array comprising a plurality of support structures, the support array being configured to support the lens array and fix a distance from the lens array to the light detector, the support array comprising a plurality of channels through which the spatially-encoded spectrum passes, the plurality of channels being defined with the plurality of support structures, wherein the diffuser, the filter matrix, and the lens array, the support array, and the detector form a light path, the light path passing sequentially through the diffuser, the filter matrix, the lens array, the support array, and ending at the light detector; wherein the light path from the diffuser to the detector is less than 9mm, wherein the resolution of the spectrometer is less than 10nm, wherein the filter matrix comprises interference filters, wherein the light path comprises a plurality of isolated optical paths extending from the filter matrix through the lens array to the multiple sensor regions, wherein each isolated optical path of the plurality of isolated optical paths is established from a single filter of the filter matrix to a single aperture of the aperture array to a single lens of the lens array to a single channel of the support array to a sensor region of the image detector, and wherein the plurality of isolated optical paths is established at least in part by the plurality of apertures of the aperture array being formed in a non-optically transmissive material thereby to prevent cross talk between the filters of the filter matrix.