All night Daylight Detector in an enclosed space emits short Redstone impulses. A day in an enclosed space, it constantly emits Redstone signal. Daylight Detector in an enclosed space day shall not emit light, and at night should emit a signal.

How to reproduce:
1. Dig a hole in depth 2 blocks.
2. Put to the bottom Daylight Detector.
3. Сlose the hole with Redstone lamp.
4. Make a day.
5. Before make a night.