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A inajor portion of the program is the development of techniques using the scanner to reveal solar cell quantities of interest, such as emitter sheet resistance and portions of the metallization making poor ohmic contact to the underlying emitter. A technique simpler than one using light modulated at high frequencies (described in the previous Quarterly Report [1] ) to reveal these quantities was instrumented during the present quarter.It employs forward biasing of the cell during scanning.The case of scanning between parallel emitter metallization stripes using a line of unmodulated light was analyzed. The analysis takes a form quite similar to that employed last quarter for the case of microwave-modulated light. It is shown for the present case that the minimum-to-maximum signal ratio depends only on the emitter sheet resistance, the stripe separation, and the cell conductance per unit area; the last can be 1 varied by adjusting the cell current. The analysis predicts that the emitter sheet resistance can be obtained by fitting the analytical value for the minimum-to-maximum ratio to the experimentally observed ratio.

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