EI source journals generally take about 3 months, and some are longer. China Journal of Scientific Instruments was an external reviewer of three experts, but one of them was rejected. China Journal of Scientific Instruments quickly rejected the manuscript. The shortest record I know is 10 days after 300 yuan paid the review fee. Employment is very slow, and it takes about 8 months from submission to the end of external audit, to modification as required, to final audit and finally to receipt of employment notice. The Journal of Photoelectric Laser or Optical Precision Engineering has been unclear. If you are a master student, there is no need to invest in EI source journals. Optical engineering may be more suitable for you. Optical engineering was also included in EI journals before March 2009. EI was kicked out after adjustment, but it is still a national first-class periodical, which is better than the three EI source periodicals you proposed.