Reflection mode volume holographic optical elements (vhoes)

A reflection mode lens, comprising:

• an input reflection mode volume holographic optical elements (VHOE) configured to accept broadband light at an angle of incidence and diffract the light at one or more center wavelengths and non-overlapping bandwidths and transmit other wavelengths to form a first reflected beam at the angle of incidence and a first diffracted beam at an Nth order diffraction angle where N is not zero and where the diffraction angle is not equal to the angle of incidence;
• and
• an output reflection mode VHOE positioned parallel to and offset from the input reflection mode VHOE such the first reflected beam bypasses the output reflection mode VHOE and the first diffracted beam is incident at the Nth order diffraction angle where the light is diffracted to form a second diffracted beam that travels a path at the angle of incidence and parallel the broadband light, and a second reflected beam that travels a different path;
• wherein the input reflection mode VHOE induces angular dispersion in the first diffracted beam
• wherein the output reflection mode VHOE introduces the same magnitude angular dispersion but of the opposite direction to compensate for and cancel the angular dispersion introduced by the input reflection mode VHOE such that the second diffracted beam has minimal axial chromatic aberration.

A method of fabricating a reflection mode composite lens for receiving broadband light at an angle of incidence, comprising:

• interfering a collimated reference beam and an object beam at angles with respect to a surface normal of a recording media equal to the angle of incidence and an Nth order diffraction angle, respectively, on opposite sides of the recording media to record a diffraction pattern on the recording media with fringes of the diffraction pattern substantially parallel to a top surface of the recording media to form an input reflection mode VHOE, said diffraction pattern configured to accept broadband light at the angle of incidence and diffract light at a center wavelength and bandwidth and transmit other wavelengths to form a first beam from the diffracted light with a principal ray at the Nth order diffraction angle where N is not zero and where the Nth order diffraction angle is not equal to the angle of incidence of broadband light;
• and
• interfering a collimated reference beam and an object beam at angles with respect to a surface normal of a recording media equal to the Nth order diffraction angle and the angle of incidence, respectively, on opposite sides of the recording media to record a diffraction pattern on the recording media with fringes of the diffraction pattern substantially parallel to a top surface of the recording media to form an output reflection mode VHOE, said diffraction pattern configured to accept the first beam from the input reflection mode VHOE at the Nth order diffraction angle and diffract light at the center wavelength and bandwidth to form an output beam from the diffracted light with a principal ray at the angle of incidence of the broadband light.