Table 2. Delay time of n pair of UST elements for focusing.

Index	Delay (s)	Index	Delay (s)	Index	Delay (s)	Index	Delay (s)
1	7.0319×10−6	9	6.2934e×10−6	17	4.5494×10−6	25	2.2505×10−6
2	7.0103×10−6	10	6.12×10−6	18	4.285×10−6	26	1.9395×10−6
3	6.9673×10−6	11	5.9318×10−6	19	4.0129×10−6	27	1.6245×10−6
4	6.9033×10−6	12	5.73×10−6	20	3.7337×10−6	28	1.3058×10−6
5	6.8188×10−6	13	5.5155×10−6	21	3.4481×10−6	29	9.8385×10−7
6	6.7147×10−6	14	5.2893×10−6	22	3.1565×10−6	30	6.5872×10−7
7	6.5918×10−6	15	5.0523×10−6	23	2.8594×10−6	31	3.307×10−7
8	6.451×10−6	16	4.8054×10−6	24	2.5573×10−6	32	0