Case 13051/13336/14411

Solar energy at greater than 50% efficiency via Polychromatic-Diffractive Concentrators


Light trapping, solar concentrator, solar cell, polychromatic diffractive lenses, dichromatic lens, spectral splitting, semiconductors


Solar (photovoltaic) cells, solar-thermal cells

  • Low energy conversion efficiency due to fixed band-gap of semiconductors.
  • Disadvantages of conventional multi-junction cells, such as undesirable absorption, current-matching constraint, lattice mismatch, high costs, etc.


The subject invention is a novel device that comprises solar cells and also includes an optical structure that concentrates and separates sunlight into a plurality of spectral bands. Each spectral band is directed to a photovoltaic cell, whose bandgap is optimized to convert that band into electric power very efficiently. The optics employ a specially designed thin concentrator element that is designed via nonlinear optimization.

  • Greater than 50% sunlight-to-electricity conversion efficiency. This has the potential to lower the cost of solar power below that of power from coal. The use of multiple single-junction cells as well as concentration considerably lower cell costs.
  • Possibility of incorporating a wider input angle to minimize sun-tracking. Tracking is considerably simplified since the concentrator is thin and light.
  • Concentration and spectral splitting is achieved via a thin planar optic, that can be mass produced using manufacturing practices used in the semiconductor and LCD industries at low amortized cost.

  • Rajesh Menon(Department of Electrical and Computer Engineering, the University of Utah & Research Laboratory of Electronics, MIT) (Cases 13051 & 13336).
  • Paul Rogge (Department of Mechanical Engineering, University of California, Berkeley) (Case 13051).
  • Hsin-Yu Tsai (Department of Electrical Engineering and Computer Science, MIT) (Case 13051).

Intellectual Property:

13051: US Patent Number 8,049,963, issued on November 1, 2011

13336: US Patent Application Number 12/253626, filed on October 17, 2008

13336: PCT Patent Application Number PCT/US2009/061146, filed on October 19, 2009

13336: Australia Patent Application Number 2009305521, filed on October 19, 2009

13336: European Patent Application Number 09821382.0, filed on October 19, 2009

13336: China Patent Application Number 200980141430.2,filed on October 19, 2009

13336: Japan Patent Application Number 2011-532309, filed on October 19, 2009

13336: Korea Patent Number 10-1212926, issued on December 10, 2012

14411: PCT Patent Application Number PCT/US2011/051916, filed on September 16, 2011



Last revised: April 30, 2013

>>List of MIT Energy IP<<