Schmeisser E T
Am J Optom Physiol Opt. 1985 Oct;62(10):709-14. doi: 10.1097/00006324-198510000-00007.
Steady-state visual evoked potentials (VEP's) were recorded from four cynomolgus monkeys in response to a sinusoidally oscillating 10 degrees helium-neon laser speckle field (632.8 nm), moving vertically 2.5 degrees at 8 shifts per second. A 5-pulse flash train at the maximum permissible exposure (MPE) dose from a collimated Q-switched frequency-doubled neodymium laser (532 nm) was superimposed on the foveal stimulus and the subsequent disruption and recovery of the VEP measured. Minimal disruption of the response signal magnitude was demonstrated (0.1 greater than p greater than 0.05) which recovered within 300 ms of the termination of the pulse train. A small but significant (p less than 0.01) disruption of phase entrainment was also noted that recovered within the same period. This is contrasted with a second experiment with three monkeys in which an argon (514 nm) laser served both as the speckle stimulus source and as the shuttered flash. Exposure to collimated MPE argon radiation for 250 ms immediately depressed the VEP (97%, p less than 0.01) and showed recovery to 70% of the pre-flash baseline only after 3 s. Phase lock was also severely degraded for several seconds. These results imply that visual processing of nonacuity-limited medium contrast stimuli with broad spatial frequency content will probably not be materially affected by ultra-short pulsed laser exposure at these energy levels and frequencies. However, even safe levels of collimated continuous laser light may have severe effects on vision that could parallel flash effects seen with Xenon discharge flash lamps.
从四只食蟹猴记录稳态视觉诱发电位（VEP），以响应一个呈正弦振荡的10度氦氖激光散斑场（632.8纳米），该散斑场以每秒8次的频率垂直移动2.5度。将来自准直调Q倍频钕激光（532纳米）的最大允许暴露（MPE）剂量的5脉冲闪光序列叠加在中央凹刺激上，并测量随后VEP的中断和恢复情况。结果表明，响应信号幅度的最小中断（0.1＞p＞0.05）在脉冲序列终止后300毫秒内恢复。还注意到相位同步有一个小但显著的中断（p＜0.01），且在同一时期内恢复。这与另一项对三只猴子进行的实验形成对比，在该实验中，氩激光（514纳米）既作为散斑刺激源，又作为快门闪光。暴露于准直的MPE氩辐射250毫秒会立即使VEP降低（97%，p＜0.01），并且仅在3秒后才恢复到闪光前基线的70%。相位锁定也在数秒内严重退化。这些结果表明，对于具有广泛空间频率内容的非视力限制的中等对比度刺激，其视觉处理可能不会受到这些能量水平和频率下的超短脉冲激光暴露的实质性影响。然而，即使是安全水平的准直连续激光也可能对视觉产生严重影响，这可能与氙气放电闪光灯所产生的闪光效应类似。
