Masato Fujiwara, Naoki Takada, Hiromitsu Araki, Chun Wei Ooi, Shohei Ikawa, Yuki Maeda, Hiroaki Niwase, Takashi Kakue, Tomoyoshi Shimobaba, Tomoyoshi Ito. Gradation representation method using a binary-weighted computer-generated hologram based on pulse-width modulation[J]. Chinese Optics Letters, 2017, 15(6): 060901