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Hadden和Grundy早已在1896年对浮雕影象的产生原因进行了研究,并确切地把这归因于显影液的坚膜作用。本文对照相浮雕影象的形成和检验进行了综合性的研究。照相浮雕影象是一种乳剂厚度的变化,这种变化是由银影象周围的明胶产生收缩所引起的。由于乳剂厚度的变化,使通过乳剂的光线产生空间相的调制,因此这种浮雕影象对光学仪器的性能就会产生重要影响,其影响程度取决于光学系统的相干性。如果光学系统是非相干的,那么这只是一种几何光学的影响。然而,一般每个光学系统都具有一定的相干度,都是一种部分相干系统。因此,浮雕影象在各种光学仪器中均会产生一定的影响,如在印片机,测微密度计以及任何一种点光源的光学仪器中。对于象全息系统这样一种完全的相干系统,浮雕影象的影响就很显著。另一个很重要的问题是,浮雕影象是银影周围明胶发生物理畸变的结果,这种畸变与银影本身受到明胶作用力后所产生的畸变十分相同。因此就可料想到,浮雕影象与边缘锐度之间有一定的联系。此外,还可预想到浮雕影象可用作光束空间相的调制,与空间调幅技术相比可提高衍射效应,浮雕影象已可单独来制作全息片。照相浮雕影象也已用于密度的测量和光谱线的显微密度测量。近来,Altman建议用浮雕影象的测量方法进行高解象力板的显微密度测定。本文研究了按正弦波的间距变化进行曝光,并用一般方法加工的浮雕影象。而对洗出型(Wash—off-type)浮雕没有研究,也没有测定乳剂的平均收缩,仅测定了接近于平均收缩的空间变化。
Hadden and Grundy already studied the causes of relief images in 1896 and attributed this precisely to the hardening effect of the developer. This paper makes a comprehensive study on the formation and inspection of photographic relief images. Photographic relief images are changes in the thickness of an emulsion caused by contraction of the gelatin around the silver image. Because of variations in the thickness of the emulsion, the light passing through the emulsion is spatially modulated such that the relief image has a significant effect on the performance of the optical instrument, the extent of which depends on the coherence of the optical system. If the optical system is not coherent, then this is just a geometrical optical effect. However, generally each optical system has a certain degree of coherence and is a partially coherent system. Therefore, the relief image in a variety of optical instruments will have some impact, such as printer, micrometer and any kind of point light optical instruments. For a complete coherent system like a holographic system, the effect of the relief image is significant. Another important issue is that relief images are the result of physical distortions of gelatin around the silver, which are exactly the same distortions as the silver itself is exposed to gelatin. Therefore, it can be imagined that there is a certain connection between the relief image and the sharpness of the edge. In addition, it is also envisioned that the relief image can be used as a modulation of the spatial phase of the beam, which enhances the diffraction effect as compared to the spatial amplitude modulation technique, which has been used alone to make holograms. Photographic relief images have also been used for density measurement and spectral line density measurement. Recently, Altman suggested using the relief image measurement method for the determination of the micro-density of high-resolution plates. In this paper, we study the relief images which are exposed by the change of the pitch of the sine wave and processed by the general method. No research has been done on wash-off-type embossing, nor the average shrinkage of the emulsion, but only the spatial variation near the average shrinkage has been measured.