(DE4213391-A)      Cell comprises: (i) an InP substrate having upper and lower surfaces; (ii) a first photoactive subcell on the upper surface of the substrate, comprising GaInAs and including a homojunction; (iii) a second photoactive subcell on the first subcell, comprising InP and including a homojunction; and (iv) an optically transparent prismatic cover layer over the second subcell. The GaInAs is lattice matched with InP; and the second subcell has a larger energy bandgap than the first subcell.    USE/ADVANTAGE -   The monolithic tandem photovoltaic solar cells are efficient, radiation resistant and useful in space applications, as well as terrestrial applications. The cell has an improved power-to-mass ratio and includes a unique middle contact region between the two subcells    (FR2675950-A1)      Cell comprises (i) an InP substrate having upper and lower surfaces; (ii) a first photoactive subcell on the upper surface of the substrate, comprising GaInAs and including a homojunction; (iii) a second photoactive subcell on the first subcell, comprising InP and including a homojunction; and (iv) an optically transparent prismatic cover layer over the second subcell. The GaInAs is lattice matched with InP, and the second subcell has a larger energy bandgap than the first subcell.    USE/ADVANTAGE -   The monolithic tandem photovoltaic solar cells are efficient, radiation resistant and useful in space applications. The cell has an improved power-to-mass ratio and includes a unique middle contact region between the two subcells    (US7689566-N)      Single-crystal, monolithic, tandem, photovoltaic solar cell includes an InP substrate having upper and lower surfaces; a first photoactive subcell on the substrate; a second photoactive subcell on the first; and an optically transparent prismatic cover layer over the second subcell.    The first subcell is GaInAsP of defined compsn., the second is DnP and both subcells are lattice matched.    USE/ADVANTAGE -   Used in space and terrestrial applications. The cells are efficient and radiation resistant.    (US5322572-A)      A single crystal, monolithic, tandem, photovoltaic solar cell comprises: (a) an InP substrate having upper and lower surfaces; (b) a first photoactive subcell on the upper surface of the substrate; the first subcell comprises GaInAs; the first subcell includes a homojunction; (c) a second photoactive subcell on the first photoactive subcell and comprises InP and includes a homojunction; and (d) an optically transparent prismatic cover layer over the second subcell. The GaInAs is lattice matched with the InP. The second subcell has a larger energy band gap than the first subcell. The solar cell further includes a top contact grid pattern over the second subcell and is in low-resistance ohmic contact with it. The cover layer includes nodes which are in alignment with the grid pattern. The cell further comprises layers of GaInAs and InP between the grid pattern and the second subcell.    USE/ADVANTAGE -   These cells are useful in space applications as well as terrestrial applications. The cells are efficient and highly radiation resistant, and have improved power-to-mass ratio.