N3 (deep or slow-wave sleep). REM sleep is distinct from non- REM sleep in three main ways: the namesake rapid eye movements, changes in respiration pattern...

https://www.apple.com/jp/healthcare/docs/site/Estimating_Sleep_Stages_from_Apple_Watch_Sept_2023.pdf

iTech* • Lishen • Luen Fung Group • Luxshare-ICT • Nidec • Nitto Denko Corporation* • OFILM* • Pegatron • Phone In Mag-Electronics* • Primax Group • Qorvo •...

https://www.apple.com/jp/environment/pdf/Apple_Supplier_Clean_Energy_Program_Update_2020.pdf