REFLECTED-LIGHT MICROSCOPY 



135 



originated from F, passes through the lens C, is reflected on the 45^ 

 slanted plate, passes through the objective O^ and is reflected on the 

 object P. Thus is the diaphragm F imaged under the object at F". 

 The hght-rays pass again through the objective O^ which images F' 

 on the phase-plate Q. The image P' of object P is observed through 

 the eyepiece O2. 



The Frangon and Nomarski layout 



The variable-absorption reflecting phase-plate (Chap, II, § 6), can 

 be used for reflected-light observation. Figure 4.9 shows the in- 

 strument's layout. The illuminator, similar to the one shown in 



Fig. 4.9. Fran^on-Nomarski device. 



Fig. 4.3, comprises the sHt F next to the lens Ci. The lens Co images 

 the slit F 2ii F' . This image is in the focus of the objective O^ and 

 the rays, illuminating the specimen P, form a beam of parallel rays. 

 The rays are reflected back by P on the lens L^ which images F', 

 i.e. F, on the phase-plate Q. The lens Z,2, is so arranged as to image P 

 at P" after being reflected on the phase-plate. 



10 



