拖尾測量測試卡簡介
拖尾測量測試卡YE0175設計用于測量在區(qū)域右側或下方的黑色區(qū)域中的視頻電平引起的干擾。由水平白色線條排列在黑色背景上組成。
拖尾測量的定義
測量由在區(qū)域右側或下方的黑色區(qū)域中的視頻電平引起的干擾。該干擾的特征在于，在恢復對應于黑色的正常視頻電平的視頻電平之前，測量延遲的持續(xù)時間。
測量設備
視頻電平表B / W監(jiān)視器，示波器，低通濾波器：500 KHz
測量條件
必須調整圖表照明，使白條給出平均光圈設置為100％的信號。
增益：0dB
伽馬校準：OFF
輪廓校準：OFF
膝部校準：OFF
基座=標稱視頻電平的5％（= 35 mV）
測量程序
在示波器上顯示穿過白線的線，并在R，G，B輸出端進行測量。重復測量以確認在各種情況下監(jiān)視器上觀察到的條紋性質。為了區(qū)分過曝的效果和條紋的效果，可以將不受穿過白色表面的僅受過曝影響的線的數目作為參考進行不同的測量。
結果介紹
條紋中黑色電平的最大峰值偏差與條紋外部的相鄰黑色相比。必須小心避免白色條紋的過曝效應。結果以標稱幅度700 mV / 75Ω的百分比給出。
The YE0175 is designed for measurement of the disturbance caused by the video level in black areas to the right of or below the areas. Horizontal white lines are positioned on a black background.
Definition of streaking measurements
Measurement of the disturbance caused by the video level in black areas to the right of or below the areas.The disturbance is characterized by measuring the duration of the delay before the video level corresponding to the normal video level of the black is restored.
Measuring equipment
Video level meter; B/W monitor, oscilloscope, low-pass filter: 500 KHz
Measurement conditions
The chart illumination must be adjusted so that the white bars give a signal of 100% with average iris setting.
Gain: 0dB
Gamma corrector: OFF
Contour corrector: OFF
Knee corrector: OFF
Pedestal = 5% of nominal video level (= 35 mV)
