[Significant Decline in Optical Communication Sector Pre-Market, COHR and MRVL Down About 5%] BlockBeats reports that on August 18, according to BIT (bit.com) market data, the optical communication sector in the U.S. stock market experienced a significant decline pre-market, including: - Roundhill Optical Module ETF (LYTE) down 4.3%; - Pure Photonics ETF FOTO down 4.2%; - Corning (GLW) down 4.48%; - Coherent (COHR) down 5.76%; - Marvell Technology (MRVL) down 4.7%; - LITE (Lumentum Holdings) down 4.52%; - CIEN (Ciena Corporation) down 3.2%.