Danish exhibitors talk at the 20th China International Optoelectronic Expo that kicked off at the Shenzhen Convention and Exhibition Center in Futian District yesterday. The four-day fair, which marks its 20th anniversary this year, brings together 1,700 enterprises from more than 30 countries and regions to showcase the most advanced solutions and applications in the field of optoelectronics.    (Story on P4)Sun Yuchen