Table 2.

Parameters of the optimized 20-in. Dynode-MCP-PMT.

Item	Parameter	Optimized design
Glass envelop	Major axis/mm	ϕ 508
	Minor axis/mm	ϕ 360
	Handle diameter (Dh)/mm	ϕ 300
Electrode I	Outer diameter (DI-out)/mm	ϕ 360
	Inner diameter (DI-in)/mm	ϕ 70
	Bias voltage (UI)/V	0
Electrode II	diameter (DII)/mm	ϕ 170
	Bias voltage (UII)/V	1600
Dynode	diameter (Dd)/mm	ϕ 70
	Bias voltage (Ud)/V	1000