The liquid crystal display (LCD) maker for smartphones, which gets more than half of its revenue from Apple, posted a net loss of 83.27 billion yen ($786.53 million) in the April-June quarter, far wider than the 1.77 billion loss a year earlier.
Japan Display, money-losing for the past five years, declined to give a full-year earnings outlook, but has previously warned it cannot guarantee a return to profit this year as demand for smartphone screens stays weak.
Apple said last week sales of the smartphone fell 12% globally to $25.99 billion in the quarter to June, after a 17% drop in the prior quarter.