In view of the refined optical correction of this condenser it is essential that it should be accurately centred and focussed.

To ensure this the Reflecting Condenser A is fitted with a Centring Device.

Since the illumination of the object is produced through the agency of rays comprised within an apertural zone of 1 to 1,35, N. A. it becomes necessary to stop down lenses of high apertures, such as immersion lenses, to about 0,9, so as to obviate the entrance into the objective of direct rays. This is effected by means of a conical stop.

The funnel Stop, as shown in the annexed illustration, consists of the body of an objective mount with the funnel stop proper screwed in, over which screws the nickel-plated part of the lens mount.

In addition to the standard pattern of the Concentric Reflecting Condenser, as described above, we supply it mounted on a plate fitted with object clips. In this form it is simply laid on the stage of the microscope and held in position by means of the stage clips. This pattern will be referred to as the Reflecting Condenser B.

Funnel Stop.

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Le texte affiché peut comporter un certain nombre d'erreurs. En effet, le mode texte de ce document a été généré de façon automatique par un programme de reconnaissance optique de caractères (OCR). Le taux de reconnaissance estimé pour cette page est de 99,63 %.

La langue de reconnaissance de l'OCR est l'Anglais.

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