Even if you intend to expose using a small aperture, a lens with a large maximum aperture can greatly increase viewfinder brightness.

即便你打算使用小光圈照相，带有最大光圈的镜头也可以在取景时大大增加取景器亮度。

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Thermal imaging systems based on uncooled focal plane array detectors require their optical lens with a large relative aperture.

基于非致冷焦平面阵列探测器的热成像系统，要求光学系统具有足够大的相对孔径。

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It features a 1.2MP front camera for video conferencing and an 8MP rear camera with a large F2.2 aperture, 5-element lens allows for high quality images along with HD video recording.

ENGADGET: ASUS rebrands its tablets 'Transformer Pads,' announces the high-end Infinity Series with either Tegra 3 or Snapdragon's S4 chip

Its newly designed, large-aperture, 4x optical zoom lens (with the maximum aperture of F2.0 at wide-angle end), high-sensitivity, back-illuminated 16 megapixel CMOS image sensor, and sensor-shift Shake Reduction system ensure sharp, high-quality, low-noise images.

ENGADGET: Pentax expands ruggedized series with Optio WG-3, Target-exclusive WG-10

The Transformer Pad Infinity has a 2MP front camera for HD video conferencing along with an 8MP rear camera with a large F2.2 aperture, 5-element lens and LED flash for stunning high quality images or HD video capture.

ENGADGET: ASUS rebrands its tablets 'Transformer Pads,' announces the high-end Infinity Series with either Tegra 3 or Snapdragon's S4 chip