Lighting device

摘要

Provided is a lightweight flexible lighting device with excellent durability and stable performance over repeated use that combines an organic electroluminescent element, an organic photoelectric conversion element, and a secondary cell. The lighting device has a control means for controlling the electrical connections of the organic electroluminescent element, the organic photoelectric conversion element, and the secondary cell. The control means controls the electrical connections such that a reverse bias voltage is applied to the organic electroluminescent element when the organic electroluminescent element receives light, generates power, and charges the secondary cell, and such that a reverse bias voltage is applied to the organic photoelectric conversion element when the organic electroluminescent element is supplied with power from the secondary cell and emits light.

主权项

1. A lighting device comprising:
an organic photoelectric conversion element; an organic electroluminescence element; a secondary cell; an electrical connection which connects the organic photoelectric conversion element, the organic electroluminescence element, and the secondary cell to each other; and a control section which controls the electrical connection,wherein the control section controls the electrical connection so that, when the organic photoelectric conversion element receives an outer light to generate electricity and charges the secondary cell, a reverse bias voltage is applied to the organic electroluminescence element, and, when the organic electroluminescence element is supplied with electric power from the secondary cell to emits light, a reverse bias voltage is applied to the organic photoelectric conversion element,
wherein the control section switches, on charging the secondary cell, the connection of the secondary cell from the organic photoelectric conversion element to the organic electroluminescence element when charging voltage of the secondary cell becomes higher than or equal to overcharge protection voltage, and wherein, when the charging voltage of the secondary cell reaches the overcharge protection voltage, electrical current is discharged to the organic electroluminescence element until the charging voltage decreases to a predetermined voltage which is lower than the overcharge protection voltage.