There are several advantages to using tempered glass and it should be the only glass used in safety applications and applications that require a lot of temperature changes (such as freezing and heating). Tempered glass is 4-5 times stronger than regular glass.
A visual migraine is a temporary visual distortion that often begins with a small sparkling, shimmering area that slowly expands outward. The growing spot often has jagged, zig-zag edges. The visual symptoms typically last approximately 20-30 minutes and then completely resolve.
WebMD Symptom Checker helps you find the most common medical conditions indicated by the symptoms flickering lights in vision, headache and sudden flash of lights including Migraine headache (adult), Tension headache, and Ocular migraine.