Lembares A, Hu X H, Kalmus G W
Department of Physics, East Carolina University, Greenville, North Carolina 27858, USA.
Invest Ophthalmol Vis Sci. 1997 May;38(6):1283-7.
To study the corneal absorption in the far ultraviolet (UV) region between 260 and 190 nm.
Thirty-four corneal samples of thickness near 20 microns were obtained from 18 porcine corneas and six human corneas with a microtome-cryostat. The authors conducted absorbance measurements of the sectioned corneal samples supported by two UV optical windows from 350 to 190 nm using a dual-beam spectrophotometer. Three whole porcine corneas were used to study the effect of freezing on the absorbance from 350 to near 290 nm.
The absorption spectra of porcine and human corneas from 350 to 190 nm were measured and three segments in the spectrum between 260 and 190 nm have been identified. The linear absorption coefficients were determined to be 2300 +/- 330 (cm-1) at 210 nm and 2410 +/- 370 (cm-1) at 193 nm for the porcine corneas and 2320 +/- 470 (cm-1) at 210 nm and 2340 +/- 150 (cm-1) at 193 nm for the human corneas.
A "window of ablation" in the far UV region between 220 and 190 nm has been identified in which short laser pulses of similar durations and different wavelengths may be interchangeable to ablate the corneal surface with similar characteristics.
研究260至190纳米远紫外（UV）区域的角膜吸收情况。
使用切片机 - 低温恒温器从18只猪角膜和6只人角膜获取34个厚度接近20微米的角膜样本。作者使用双光束分光光度计对由两个紫外光学窗口支撑的切片角膜样本在350至190纳米范围内进行吸光度测量。使用三个完整的猪角膜研究冷冻对350至近290纳米吸光度的影响。
测量了猪角膜和人角膜在350至190纳米的吸收光谱，并确定了260至190纳米光谱中的三个波段。猪角膜在210纳米处的线性吸收系数测定为2300±330（cm⁻¹），在193纳米处为2410±370（cm⁻¹）；人角膜在210纳米处为2320±470（cm⁻¹），在193纳米处为2340±150（cm⁻¹）。
已确定在220至190纳米的远紫外区域存在一个“消融窗口”，在该窗口中，持续时间相似但波长不同的短激光脉冲可能可以互换，以消融具有相似特征的角膜表面。
