Late-Táng court philologist, fl. 833–837 (Tàihé 7 to Kāichéng 2). Held the office Hànlínyuàn dàizhào 翰林院待詔 under Wénzōng. Native place not recorded. By imperial command in Tàihé 7 (833) he was tasked with verifying the orthography for the engraving of the Kāichéng shíjīng 開成石經; he produced the Jiǔjīng zìyàng 九經字樣 KR1j0025 in 1 juàn, 421 graphs in 76 bù, expressly as a supplement to Zhāng Shēn’s 張參 earlier Wǔjīng wénzì KR1j0024. The Jiǔjīng zìyàng was inscribed on stone after the Nine Classics in Kāichéng 2 (837); the rubbing is the principal source of the modern text. He is also notable for substituting X píng / X shàng tone-rotation glosses for the older fǎn notation — the Sìkù tíyào identifies him as the figure who shifted Táng phonological notation from fǎn 反 to qiè 切. No CBDB entry; biography is reconstructed entirely from the Tang huìyào and his own preface.