Method of composing half-tone pictures by means of electronic phototype setters

Claim 1

The method of composing rastered continuous pictures by means of electronic phototype setters operating by rastering comprising: forming characters to be stored; electro-optically scanning said characters and converting said scanned data into a binary code in which the tonal range from white to black is divided into a finite number of grey stages which are increasingly shaded according to a predetermined nonlinear function corresponding to the perception of the human eye and the stages are numbered and binary coded and to each code number there is allocated a raster field whose surface is covered with black corresponding to the tonal value; storing said data in a memory with predetermined address; and controlling said phototype setter with data from said memory under the control of a suitable program.

Claim 2

The method of composing rastered continuous pictures by means of electronic phototype setters operating by rastering comprising: forming characters to be stored; electro-optically scanning said characters and converting said scanned data into a binary code in which the tonal range from white to black is divided into a finite number of grey stages which are increasingly shaded according to a predetermined nonlinear function corresponding to the perception of the human eye and the stages are numbered and binary coded and to each code number there is allocated a raster field whose surface is covered with black corresponding to the tonal value; storing said data in a memory with predetermined address; and controlling said phototype setter with data from said memory under the control of a suitable program.

Claim 5

A method for composing rastered continuous tone pictures by means of electronic phototype setters operating by rastering, wherein the tonal range from white to black is divided into a finite number of grey stages which are increasingly shaded according to a predetermined non-linear function, the stages are numbered and binary coded and to each code number there is allocated a raster field whose surface is covered with black corresponding to the tonal value, and these raster fields are stored as manually constructed character pictures in electronic form in the memory storage of a composing apparatus, the continuous tone picture original to be composed is photoelectrically scanned dot by dot, in successive lines at distances which are the same as the distances between raster fields, the tonal value encountered is quantized and the raster number allocated thereto is determined, and the corresponding raster information is read out from the memory of the phototype setter for recording the raster dot on the picture screen of a cathode ray tube, wherein, in order to obtain the different tonal values the black covering of the raster field is dimensioned according to a function which corresponds to the power of perception of the human eye.

Claim 6

A method for composing rastered continuous tone pictures by means of electronic phototype setters operating by rastering, wherein the tonal range from white to black is divided into a finite number of grey stages which are increasingly shaded according to a predetermined non-linear function, the stages are numbered and binary coded and to each code number there is allocated a raster field whose surface is covered with black corresponding to the tonal value, and these raster fields are stored as manually constructed character pictures in electronic form in the memory storage of a composing apparatus, the continuous tone picture original to be composed is photoelectrically scanned dot by dot, in successive lines at distances which are the same as the distances between raster fields, the tonal value encountered is quantized and the raster number allocated thereto is determined, and the corresponding raster information is read out from the memory of the phototype setter for recording the raster dot on the picture screen of a cathode ray tube, wherein, in order to obtain the different tonal values the black covering of the raster field is dimensioned according to a function which corresponds to the power of perception of the human eye.

Claim 12

A method for composing rastered continuous tone pictures by means of electronic phototype setters operating by rastering, wherein the tonal range from white to black is divided into a finite number of grey stages which are increasingly shaded according to a predetermined non-linear function corresponding to the perception of the human eye and the stages are numbered and binary coded and to each code number there is allocated a raster field whose surface is covered with black corresponding to the tonal value, and these raster fields are stored as manually constructed character pictures in electronic form in the memory storage of a composing apparatus, the continuous tone picture original to be composed is photoelectrically scanned dot by dot, in successive lines at distances which are the same as the distances between raster fields, the tonal value encountered is quantized and the raster number allocated thereto is determined, and the corresponding raster information is read out from the memory of the phototype setter for recording the raster dot on the picture screen of a cathode ray tube.

Claim 13

A method for composing rastered continuous tone pictures by means of electronic phototype setters operating by rastering, wherein the tonal range from white to black is divided into a finite number of grey stages which are increasingly shaded according to a predetermined non-linear function corresponding to the perception of the human eye and the stages are numbered and binary coded and to each code number there is allocated a raster field whose surface is covered with black corresponding to the tonal value, and these raster fields are stored as manually constructed character pictures in electronic form in the memory storage of a composing apparatus, the continuous tone picture original to be composed is photoelectrically scanned dot by dot, in successive lines at distances which are the same as the distances between raster fields, the tonal value encountered is quantized and the raster number allocated thereto is determined, and the corresponding raster information is read out from the memory of the phototype setter for recording the raster dot on the picture screen of a cathode ray tube.