zemax中Afocal Image Space選項的作用-無焦模式

2020-02-14 by:CAE仿真在線來源:互聯(lián)網(wǎng)

在zamax中,該選項在系統(tǒng)設(shè)置里面或system exporter》》aperture里面進行控制。

Afocal Image Space

If this box is checked, OpticStudio will perform most analysis features in a manner appropriate for optical systems with output beams in image space that are nominally collimated. Strictly speaking, the term afocal means the optical beam is collimated in both object and image space. However, OpticStudio uses this term to describe collimated output in image space, whether the beam is collimated in object space or not. For brevity, the documentation uses the term “afocal mode” to indicate Afocal Image Space is checked on, and “focal mode” to indicate Afocal Image Space is checked off.

When using afocal mode, transverse, longitudinal, and MTF aberrations are computed in units appropriate to afocal systems. Transverse aberrations are computed as a function of angle relative to a reference ray rather than units of length. Longitudinal aberrations are computed as a function of defocus in diopters (inverse meters) rather than as defocus in units of length. MTF is measured in cycles per angle rather than cycles per length. The change of units is not always mentioned in the documentation for each individual analysis feature. When using afocal mode, the user should be aware that some analysis window settings described in focal units are actually in afocal units if afocal mode is on. Afocal aberrations may be measured in various units, with milliradians being the default.To change the afocal unit type, see “Afocal Mode Units” in the Units Section and see the section of System Explorer.

無焦點圖像空間(無焦模式)

如果選中此框,則OpticStudio將以適合光學(xué)系統(tǒng)的方式執(zhí)行大多數(shù)分析功能,這些光學(xué)系統(tǒng)的圖像空間中的輸出光束標稱已校準。嚴格來說,術(shù)語“無焦點”是指光束在物體和圖像空間中都是準直的。但是,OpticStudio使用此術(shù)語來描述圖像空間中的準直輸出,而不管光束是否在對象空間中準直。為簡便起見,文檔使用術(shù)語“遠景模式”表示選中“焦點圖像空間”,而使用“焦點模式”來表示選中“焦點圖像空間”。

使用無焦點模式時,以適合于無焦點系統(tǒng)的單位計算橫向,縱向和MTF像差。橫向像差是相對于參考射線的角度而不是長度單位的函數(shù)。縱向像差是作為散焦度的函數(shù)(以米為單位)(而非米),而不是作為散焦的長度單位。 MTF以每個角度的周期數(shù)而不是每個長度的周期數(shù)來衡量。文檔中并不總是針對每個分析功能都提到單位的變化。使用自動對焦模式時,用戶應(yīng)注意,如果打開了自動對焦模式,則焦點單位中描述的某些分析窗口設(shè)置實際上是以自動對焦單位為單位?？梢允褂枚喾N單位來測量總像差,默認設(shè)置為毫弧度。要更改總焦類型,請參閱“單位”部分中的“ Afocal模式單位”,并參見“系統(tǒng)資源管理器”部分。

在一個激光擴束鏡頭系統(tǒng)的優(yōu)化案例中,入射光和出射光相互平行,這個時候就需要無焦點限制。

這個限制不會限制你的鏡頭系統(tǒng)的設(shè)置,只會對優(yōu)化過程和優(yōu)化目標有影響。

有的同學(xué)說這個限制應(yīng)該做在merit function里面,但實際上zemax把他當做一個系統(tǒng)設(shè)置項目。

其作用很可以通過下列兩個效果圖來對比: