BAIRD &.TATLOCK. (LONDON) LTD. 





Optical Projection Screens with Metallic Surface. Screens for Optical projection, 

 with metallic surface for coloured and feebly lighted pictures. 



Within the hist few years optical projection has come very much to the front as a means of instruction ami 



ertainment, and this valuable and fascinating method of demonstration has now entered upon a stage where 



it U-rniiirs in many cases a matter of serious difficulty to secure a sufficiently bright picture, whilst 1 here is scarcely 



possibility of remedying the defect by an improvement of the apparatus itself. As far as the power of tin- 

 i.pncal apparatus and the light producing appliances are concerned we have practically reached the extreme limit 

 of the attainable intensity, and at present there is little or no prospect of increasing the brightness of the picture 

 ( \ri-ptini; by improving the reflecting properties of the screen. 



An increase in the reflecting power of the screen may be obtained in various ways, e.g. by adopting the principle 

 ot tueinllic reflection, which should, of course, be of the nature of diffuse reflection, since a mirror cannot s-rvc a-, a 



re screen. It is accordingly necessary to employ in these cases dulled surfaces. 



(ifl'tiil Projection Screens of this kind are made at the Zeiss Optical Works. These screens have a metallic 

 surface prepared by a special registered process, and are supplied in sizes having very extensive areas. I ln-y are 

 mainly made up of aluminium, which is less readily affected by the chemical influences of the atmosphere than 

 metals, and they may be rolled up. 



PRICES AND DIMENSIONS OF METALLIC SCREENS (Registered). 

 1185 T Smooth Aluminium Screen, mounted in frame and not made to roll up : 



1. Size : 40 by 40 inches 



2. ,, 60 60 



3. 80 80 



1186 1 Seamless Aluminium Shirting Screen, mounted in frame and not made to roll up : 



4. Size : 40 by 40 inches 



5. ,, 60 60 



6. 80 80 



1187' Seamless Aluminium Shirting Screen, with folding frame, strap ends, and rolling 

 device : 



7. Size : 984 by 98^ inches 



8. 118 n8~ 



1188' Ribbed Aluminium Screen, mounted in frame and not made to roll up: 



9. Size : 40 by 40 inches 



10. ., 60 60 



11. ,, 80 80 



1189 T Combined Smooth Aluminium and Aluminium Shirting Screen for use on both 



sides, mounted in frame and not made to roll up : 



14. Size : 40 by 40 inches . . . . . . . . . . 



15. ,, 60 60 



16. So 80 



1190 T Combined Smooth, Shirting, and Ribbed Aluminium Screen with back available 

 for use as an ordinary white screen, mounted in frame and not made to roll up : 



17. Size : 40 by 40 inches. Smooth . . 



18. ,, ,, Shirting . . 



19. ,, .. Ribbed 



20. ,, 60 ,, 60 ,, Smooth .. 



21. ,, ,, Shirting .. 



22. ,, ,, Ribbed .. 



23. ,, 80 80 Smooth .. 



24. ,, ,, ,, Shirting . . 



25. ,, ,, Ribbed 



Other Screens besides those specified under No. ii8y T are supplied to order. 



1191 T Tripod Stands of Polished Wood with appliances for attaching, raising, and lowering 

 as well as for turning the screen from side to side are supplied for screens measuring up to : 



26. Size : 60 by 60 inches 



27. ,, 80 80 . . . . 



1 15 



3 1 



4 16 



1 15 



3 1 



4 16 



12 10 

 15 10 



1 18 

 380 

 580 



220 

 3 18 

 640 



200 

 200 

 230 

 3 13 

 3 13 

 400 

 5 16 

 5 16 

 680 



100 

 2 10 



.CHEMICAL AND SCIENTIFIC APPARATUS AND PURE CHEMICALS. 



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