Silicon photonics' original sin is that it can't emit light. Lasers hate heat, yet CPO asks them to sit next to a hot chip — making the light source the reliability ceiling, where one failed laser can cost an entire optical engine. External vs integrated sources and four light-source types each bet on a different future.
![[CPO Teardown 3/6] The Most Fragile Link in CPO Is the Laser](https://static.wixstatic.com/media/82206f_45e890f73e32485c8274f79ca2ec5361~mv2.png/v1/fill/w_1773,h_1000,fp_0.50_0.50,q_35,blur_30,enc_avif,quality_auto/82206f_45e890f73e32485c8274f79ca2ec5361~mv2.png)
![[CPO Teardown 3/6] The Most Fragile Link in CPO Is the Laser](https://static.wixstatic.com/media/82206f_45e890f73e32485c8274f79ca2ec5361~mv2.png/v1/fill/w_1220,h_688,fp_0.50_0.50,q_95,enc_avif,quality_auto/82206f_45e890f73e32485c8274f79ca2ec5361~mv2.png)