要提高颜色数据测量的准确和稳定性,有如下10点建议:
1. Qualified regular preventative maintenance will assure that the spectrophotometer’s integrating sphere coating is within acceptable reflectance parameters, and that the instrument continues to operate within specification.
高品质的日常保养(除尘、年校正等)可以保证积分球的涂层结构的良好状态和仪器数据的稳定性。
2. A constant temperature environment will eliminate measurement variability caused by thermal changes within the instrument. Therefore, it is best to maintain power to the spectrophotometer (to eliminate warm-up thermal drift), and to keep the room environment at nearly constant temperature.
稳定的环境温度可以提升测量稳定性。所以,建议电源常开(减少温度波动)同时保证房间的温度稳定。
3. Maintain carefully the white and black standards, since the photometric scale (0 to 100%) of the spectrophotometer is calibrated to these standards. Handle and store the white tile so that it does not become soiled or scratched. If soiled, clean the tile using water (and if necessary a mild soap), drying with a clean non-abrasive, non-optically whitened paper towel or cloth. If dirt or dust enters the black trap, clean it using a compressed air flow.
注意保持黑阱和白标准物的完整性,避免磕碰,因为仪器需要通过其进行校正。保存好白标准板,保证其干净和没有划痕。白板的清洁可以使用清水,黑阱里面的灰尘可以使用吹气装置。
4. Recalibrate more often because the photometric scale (0 to 100%) of any spectrophotometer may “drift” over time between calibrations, due to temperature, light source and/or photodetector factors. Any “drift error” is eliminated at calibration, and greatly reduced by recalibrating often.
适当频繁的黑白校正可以保证数据的准确,防止温度环境等因素对测量光源能量的漂移影响。校正可以排除这种“漂移错误”,使数据更加稳定准确。
5. The fact that pigments and dyes change their color properties as their temperature changes, is potentially a major source of errors in any color measurement operations. Almost all colorants (except white and black and some blues) change color as their temperature changes. The color changes can be significant, and are typically in the range of about 0.6 to 1.1 dE CIELAB for most high chroma colorants, for a 10 degree C temperature change. If production samples (batches) must be measured at a temperature different from that when the standard was measured, then (if possible) remeasure the standard at the new temperature.
某些产品会受到温度和湿度的影响而变色,某些样本本身温度每10摄氏度变化可以导致0.6到1.1DE的颜色变化(如绿色瓷砖、红色纺织品)。
6. Non-opaque samples usually must be measured as if they were opaque, to meet particular color application needs. In these cases, it is best to increase sample opacity by increasing sample thickness, so that the color measurement will not be influenced adversely by the “show-through” of a black (or white) background. Textile cloth can be folded multiple times, yarns and threads wound in multiple layers, and papers stacked, to meet the desired opaque (or most nearly so) requirement.
半透明材料测量时候,建议增加层数直到其不透明。也可通过保持统一测量衬垫,或统一 测量背景,保证数据的稳定性。
7. Optically directional samples (such as corduroy fabric, calendared vinyl, and card wound yarns and threads), often measure differently as they are rotated in the sample port. The directional geometric properties of these samples can result in measurement errors, whenever the standard and batch are measured differently. The measurement errors can be virtually eliminated by always measuring with the same sample orientation, or by measuring the sample 4 times (at 90 degree intervals) and averaging the data.
样本的方向性会影响测量的结果。所以为了保证测量的稳定性,建议旋转4次测量(每次转动90°)然后取平均数据。
8. Inconsistent (or irregular) samples can yield different measurements, depending upon what part of the sample is measured. This measurement variability can be greatly reduced by measuring the sample multiple times and averaging the results, moving the sample between measurements.
建议通过多次移动样本测量,并平均测量数据,可提高数据稳定性。
9. The largest viewing area available should generally be utilized, as it extends the measurement over a larger portion of the sample.
建议使用最大大孔径版(1英寸直径)测量样本。
10. Use the same viewing area for measuring the standard, as will be used in measuring production batches. This technique is desirable since different viewing areas (even of the same spectrophotometer), will typically not measure exactly the same.
标准和批样要用相同的孔径版测量,不同孔径版测量结果由于取样位置不同可能会造成差异。
11. If possible, use the same spectrophotometer, under the same conditions, to measure any samples to be compared, since no two spectrophotometers agree exactly.
如果可能请使用同一台测色仪器,相同的测量环境进行测量。因为两台仪器间总会有或多或少的差异。
总结:
良好的仪器保养状态
良好的仪器使用环境(温度湿度)
良好的黑白标准物状态
良好的样本状态(温度湿度)
建议多次校正
建议用大孔径
建议旋转测量平均
建议移动多次测量平均
建议使用相同孔径测对比物
建议使用相同仪器测对比物
2018年11月2日