问题 选择题

显微镜对光时,如果所看到的视野较暗,应选择下例哪项进行调节?( )

①较大的光圈②较小的光圈③反光镜的平面④反光镜的凹面

A.① ③

B.① ④

C.② ④

D.② ③

答案

答案:B

当视野暗时,调节反光镜,用凹面反光镜,转动遮光器,用大的光圈。

问答题

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单项选择题