Patent GB-711494-A (GB)
Title: Improvements in photographic type-composing machines and type characters therefor
IPC: B41B15/08
Filed: 1951-06-07
Abstract: 711,494. Photographic type-composing machines. INTERTYPE, Ltd. June 7, 1951 [June 8, 1950], No. 13509/51. Class 98(1) In a method of photographic type-composing machine wherein the feed or advance of the photographic material on which the type characters are to be successively recorded is controlled between successive exposures by means of elements, each having an appropriate dimension responsible for the feed and normally proportionate to the setwise width of the individual character, a secondary group of elements is provided having feed-control dimensions substantially less than those of corresponding normal elements, whereby the feed of the photographic material will be reduced when a secondary element is used in place of the corresponding normal element to cause a predetermined overhang between the character reproduced therefrom and an adjacent reproduced character on the photographic material. Where two successive characters are to be wholly superposed, elements of lesser body dimensions for each are provided, the total of such body dimensions equalling the normal body dimension of one of the elements. The photographable character on an element of lesser body dimension may be located thereon in a position offset from its normal position in line-reading direction by a distance corresponding to the difference in body dimensions of normal and corresponding secondary elements. As shown in Fig. 2, a normal element bearing the character W has a thickness of 4 units (A) and the leading edge 38a (B) of the character is a distance of 2 units above the optical axis of the type-composing machine when the element is in photographing position. The character, although assigned a setwise field of 4. units on the recording film due to the thickness of the element, has an actual setwise width slightly less to provide the intercharacter space 42. The reference line 43 is always a fixed distance 44 below the notch 31 of the element. Similar considerations apply to the letters A and T shown in Figs. 3 and 4, the successive stages of -recording the characters on the film being shown in Figs. 2C, 3C, and 4C. In order to achieve partial overlap of the image-fields of the characters to avoid undue inter-character spacing, elements 53 and 54, Figs. 6 and 7, of less than 4 and less than 3 units width respectively are provided for the characters W and A, and to avoid violation of the starting margin 45 as illustrated in Fig. 6C, and also partial overlap of the actual character images W and A as depicted in Fig. 7C, the characters are displaced on their plaques relative to their normal positions by amounts corresponding to the reduced thickness of the elements as shown in Figs. 6B and 7B. The successive stages of recording the characters with the desired overlap of the image-fields is shown in Figs. 6C to 8C. The only characters that require supplementary secondary elements of lesser thickness are A, F, L, P, T, V, W, and Y. The secondary elements are preferably reduced in thickness by one or any other integral number of thickness units to avoid the provision of elements of special thickness. Similar supplementary elements are provided for foreign language founts where the language requires composite characters, e.g. for providing basic consonant components with vowel signs in Hebrew. To achieve complete superposition, the combined thickness of the consonant and vowel elements is equal to that of a standard element for the basic consonant component, the consonant being displaced on such supplementary elements by amounts sufficient to dispose images thereof on the film in the same position as if the film had been advanced by distances corresponding to normal elements. Since the vowel signs are disposed in different positions relative to some consonants, elements with the same vowel signs dif- 'ferently located are, provided. Reversal of the line to take into account the fact that Hebrew is read from right to left is effected by printing the photographic negative obtained on development of the film on to a film with the emulsion side down. Specifications 358,144 and 650,630 are referred to.