本儀器用于測量視度值在±6.6個視度范圍內的光學儀器的視度。二、 原理本儀器是在4×視度前置鏡的基礎上增設一套（十塊）已知視度值（分別為±1，±2，±3，±4，±5個視度）的視度透鏡構成的。測量時根據(jù)被測儀器的視度，選取對應的一塊視度透鏡擰在視度筒的外管上，置于4×視度前置鏡的物鏡前。視度透鏡將被測儀器的視度先抵消一部分，致使被測視度值剩余部分在±1.5個視度范圍內，便可利用4×視度前置鏡視度刻尺測出其剩余視度數(shù)值。由視度透鏡的視度值與4×視度前置鏡測得之視度值得到被測儀器視度值。這樣，就擴大了視度的測量范圍。??? 增設的十塊視度透鏡分別裝在透鏡框內，透鏡柜上分別刻有 5D， 4D， 3D， 2D， 1D，-1D，-2D，-3D，-4D，-5D的符號和數(shù)字。三、 儀器諸元目鏡焦距??????????????????????????? 20.86mm物鏡焦距??????????????????????????? 79.9mm物鏡有效孔徑??????????????????????? 17mm視度透鏡透鏡焦距（mm） -200.04 -250.09 -333.51 -500.10 -1000.19 1000.19 500.10 333.51 250.09 200.04所用透鏡框的標記 5D 4D 3D 2D 1D -1D -2D -3D -4D -5D視度透鏡有效孔徑??????????????????? 14mm視度標尺分劃格值??????????????????? 0.25個視度視度標尺分革刻度范圍??????????????? ±1.5個視度測量范圍??????????? ????????????????±6.5個視度外管刻線格值??????????????????????? 1mm外管刻線范圍??????????????????????? 25mm var taFace = null; function FaceInit() { taFace = document.getElementsByTagName('textarea')[0]; taFace.setAttribute("onkeydown", "TraceCursorPosition(this)"); taFace.setAttribute("onkeypress", "TraceCursorPosition(this)"); taFace.setAttribute("onfocus", "TraceCursorPosition(this)"); taFace.setAttribute("onselect", "TraceCursorPosition(this)"); taFace.setAttribute("onmouseover", "TraceCursorPosition(this)"); taFace.setAttribute("onmousedown", "TraceCursorPosition(this)"); } function FaceShow() { if(taFace == null) FaceInit(); if (document.getElementById('dFace').style.display == 'none') { document.getElementById('dFace').style.display = 'block'; } else FaceHide(); } function FaceHide() { document.getElementById('dFace').style.display = 'none'; } var pFace; function Face(text) { if (!pFace) TraceCursorPosition(taFace); taFace.value = taFace.value.slice(0, pFace.start) +"[:" + text + ":]" + taFace.value.slice(pFace.end); FaceHide(); } function TraceCursorPosition(obj) { pFace = $CursorPosition(obj); } function $CursorPosition(textBox) { var start = 0, end = 0; if (typeof (textBox.selectionStart) == "number") { start = textBox.selectionStart; end = textBox.selectionEnd; } else if (document.selection) { var range = document.selection.createRange(); if (range.parentElement().id == textBox.id) { var range_all = document.body.createTextRange(); range_all.moveToElementText(textBox); for (start = 0; range_all.compareEndPoints("StartToStart", range) < 0; start++) range_all.moveStart('character', 1); var i; for (i = 0; i 以上是大量程視度管的詳細信息，如果您對大量程視度管的價格、廠家、型號、圖片有什么疑問，請聯(lián)系我們獲取大量程視度管的新信息。