An optical thickness of less than 0.1 indicates a clear sky with maximum visibility; a value of 1 or above indicates very hazy conditions.

光学厚度小于0.1意味着是能见度高的晴天；1或者以上则意味着烟雾天气。

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The three are all optical satellites, which can capture images in daylight and in clear weather.

这三颗卫星均为光学卫星，它们可以在白天和良好天气下抓拍图像。

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As one of the most important parts in optical components, reflect-mirror was the key technology in laser communication and provided clear imaging for the system.

反射镜作为系统中的重要光学元件，也是激光通信中的关键技术，为整个通信系统的像质提供了保证。

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Panasonic's Advanced OIS detects and corrects for hand-shake around 4, 000 times per second and works with the high-powered optical zoom to produce clear, stable zoom shots.

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Still, this was pretty clear, almost no ultraportables have optical drives.

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Thanks to observations made with the Gemini ground-based optical telescope in Hawaii, it quickly became clear that GRB130427A was superbright primarily because it lay only a few billion light years away.

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