Optical elements, color combiners using the optical elements, and image projectors using the color combiners are described. The optical elements can be configured as color combiners that receive different wavelength spectrums of light and produce a combined light output that includes the different wavelength spectrums of light. In one aspect, the received light inputs are unpolarized, and the combined light output is polarized in a desired state. The optical elements are configured to minimize the passage of light which may be damaging to wavelength-sensitive components in the light combiner. Image projectors using the color combiners can include imaging modules that operate by reflecting or transmitting polarized light.