JPS60122947A - Manufacture of printing film for adjusting night illumination of indicating meter - Google Patents

Abstract

PURPOSE:To obtain easily a necessary printing density irrespective of characteristics of a negative film and printing by bringing a negative film which has photographed an unbalance of illumination as it is, to halftone resolution by a color scanner, and preparing a printing negative. CONSTITUTION:An illuminance adjusting printing film 9 is provided on the rear side of a number plate 1 formed by a transparent resin of an indicating meter, and illuminated by an illuminating lamp 8. With respect to the illuminating lamp 8, a film is placed instead of the number plate 1, the illuminating lamp 8 is lighted, and an unbalance of illumination is photographed as it is and developed. Its negative film is brought to halftone resolution by a color scanner, and a negative is prepared. From its negative, an illuminance adjusting printing film 1 is prepared. In this way, a necessary printing density is obtained easily irrespective of characteristics of the negative film and printing.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a nighttime indicator 11 of an indicator mainly used for automobiles.
The present invention relates to a method of manufacturing a printed film applied to the back surface of the dial of an indicating instrument in order to equalize the illuminance of six bright lights.

[Prior art]

FIG. 1 shows a cross section of an indicating instrument that has been widely used in the past, and FIG. 2 is a front view of its dial. As shown in the figure, the dial l is fixed to an inner tab 3 attached to the case 2, and its surroundings are shielded by a facing plate 5. The dial plate 1 is made of a transparent resin such as acrylic, and the number 6, scale 7, etc. are printed on its surface with light-transmitting ink, and other parts are printed with black ink. 8 is an illumination lamp attached to the case 2. Further, a printed film 9 for illuminance adjustment is implemented on the back side of the dial 1, and as shown in FIG. 3, this back side printing 1! ! The original printing plate 12 for 9 is
As is clear from Japanese Patent Publication No. 53-2065, it is made from a negative film 10 and a contact screen 11 that capture the unevenness of the illumination at the position of the dial l, but in places with bright illumination, there are large points, In dark places, small dots are formed to even out the illumination. Also, curve 1 in Figure 4
9 shows the printing characteristics of the back printing film 9, which is expressed by the relationship between print density and original halftone dot %. Also, curve 2 in Figure 5
0 indicates the relationship between the density of the negative film IO and the halftone dot % of the original plate 12, which is determined by the characteristics of the contact screen 11. Moreover, FIG. 7 shows the general characteristics of negative film. FIG. 6 shows the relationship between the illumination intensity necessary to make the illumination intensity uniform and the density of the printed matter, and the relationship shown in FIG. 6 will be briefly explained. Print density As
, If the target illuminance to be made uniform is IO1, and the unbalanced illuminance before being made uniform is I, then the printing density required to make the illuminance uniform from ■ to ■0 is As=l.

g(+/io). That is, As=Iogl-1og
io, and since 10 is constant, the characteristic in FIG. 6 is a straight line 21 at 45° around 1. In other words, the necessary printing density is determined from the relational characteristics shown in FIG.

Here, the method of obtaining a predetermined density of the back side printing 9 is briefly described in Japanese Patent Publication No. 53-2065 as mentioned above, but the details of the process are as follows: ■ Shooting of negative film lO, ■ Contact screen 11, and (1) the order of printing. Examining this process qualitatively and quantitatively, we can see that the negative film 10 is photographed and developed according to the characteristics shown in FIG. The continuous density of the film 10 is divided into the sizes of halftone dots, and then printing is performed according to the characteristics shown in FIG. 4, and the printing density is obtained from the halftone dots.

Then, a printing density having a relationship with the illumination intensity as shown in FIG. 6 is obtained.

However, the printing characteristics shown in FIG. 4 are almost determined by the printing method, ink, type of plate, etc., and it is impossible to control the characteristics. Furthermore, the network resolution characteristics shown in FIG. 5 are determined by the characteristics of the contact screen 11. Furthermore, when comparing the characteristic curves 19 and 20 in FIGS. 4 and 5, they are not the same. Further, regarding the characteristics of the characteristic curve 23 of the negative film shown in FIG. 7, there is no degree of freedom other than the slope of the straight line portion. Therefore, in the conventional method, the characteristic shown in FIG. 6 is not an ideal straight line 21 but a curved line 22, and the illuminance cannot be made uniform. For example, 10~10j! In the case where the illuminance variation in x is made uniform to 5Jx, the required printing density is 0.3 to 1.3, and the relationship of the straight line 21 is required. However, due to the difference between characteristic 20 in FIG. 5 and characteristic 19 in FIG. Since the relationship characteristic of the variation becomes curve 22, it becomes brighter than 511x, and there is a drawback that the necessary printing density cannot be obtained.

[Purpose of the invention]

In order to solve the above-mentioned drawbacks, the present invention creates a printing original plate by subjecting a negative film photographed with unbalanced illumination as it is to halftone separation using a color scanner. The purpose is to easily obtain a high printing density.

〔Example〕

The present invention will be described below with reference to embodiments shown in the drawings.

FIG. 8 is a schematic block diagram of a so-called color scanner that has the ability to electronically perform color separation and formatting.The operating principle of a color scanner will be briefly explained using FIG. Color originals are generally attached to the
A photographic material for disassembly photographic recording is attached to the recording section 27. The scanning unit 25C1 second ζ moves the scanning light row relative to the original so as to sequentially cover the entire surface of the original, sequentially scans the original image in minute areas, and transmits or reflects the original. The luminous flux is color-separated and photoelectrically converted to obtain uncorrected color-separated electrical signals of three colors.

These signals are input to the electronic circuit section 26, where the primary and secondary color correction circuits and gradation correction circuits are adjusted to obtain the desired color and tone on the printed matter. subject to modification or transformation. The corrected decomposed signal is then supplied to the recording section 27, where the magnitude of the signal is converted into electro-optical signals and returned to the strength of a thin beam of light. The photographic materials attached to the recording section 27 are sequentially exposed to this light, thereby obtaining corrected color separation photographs. Further, when halftone dots are used to express density (1), the electronic circuit section 26 can be provided with a function of generating linear halftone dots.

Therefore, in this embodiment, the negative film 10 is attached to the scanning section 25 of the color scanner, the electronic circuit section 26 is provided with a function of directly generating halftone dots, and the photographic material for decomposed photographic recording attached to the recording section 27 is attached to the original plate 12. That is.

In this way, by using the color scanner shown in FIG. 8 for halftone separation, the characteristic curve shown in FIG.
The characteristic 24 of FIG. 6 was adjusted to the broken line, which is exactly the same as that of 9, and the characteristic of FIG. 6 was made into a straight line. Also, as explained above, the color scanner can freely change the characteristics shown in Figure 5, so if the photographing and developing conditions for the negative film 10 are different, it is possible to change the characteristics shown in Figure 7 without using only the straight line part 23a. This straight line part 23a
Even if curved portions 23b and 23b are used, the network decomposition characteristics shown in FIG. 5 can be changed so that the characteristics shown in FIG. 6 become straight lines.

The overall manufacturing method of this example will be briefly explained below. Non-uniform illuminance range I before forming the illuminance adjustment printed film 9
Determine the printing density range N1-N2 of the printing film 9 from I to 12 and the target illuminance 1o that you want to make uniform, and
After determining the density range of 0, the conditions for photographing and developing the negative film 10 are determined.

And, instead of the dial 1 in Fig. 1, a negative film IO
Then, the illumination lamp 8 is turned on, a photograph is taken according to the conditions set earlier, and the image is developed.

Next, the photographed negative film 10 is subjected to halftone separation using a color scanner to produce an original plate 12.

Then, from the original plate 12, a printing plate is produced by a generally well-known photoengraving method, although not described in detail here. By printing, it becomes possible to make the illumination uniform at the target illuminance.

〔Effect of the invention〕

As described above, in the present invention, in order to create a printing original plate for obtaining a printing film applied to the back of the dial of an indicating instrument, a negative film photographed with the unbalance of brightness and darkness as it is is scanned using a color scanner. Since it is decomposed, it is possible to easily obtain the required printing density, and the characteristics of the original halftone dot % relative to the negative film density can be freely changed, greatly increasing the degree of freedom in photographing and developing conditions for negative film. It has the excellent effect of improving

[Brief explanation of drawings]

FIGS. 1 and 2 are longitudinal cross-sectional views and plan views showing an embodiment of an indicator equipped with a printed film for adjusting night lighting produced by the conventional method and the method of the present invention, and FIG. Developed drawing for explaining the method of manufacturing the printing film original plate, No. 4
Figures 7 to 7 are examples of the characteristics of print density - original halftone dots %, negative film density - original halftone dots %, illumination illuminance - print density, and exposure amount - negative film density, which are commonly used in the conventional method and the method of the present invention. FIG. 8 is a schematic block diagram showing an embodiment of a color scanner applied to the method of the present invention. DESCRIPTION OF SYMBOLS 1... Dial board, 8... Illumination lamp, 9... Printed film for night illumination adjustment. Representative Patent Attorney Takashi Okabe

Claims (1)

[Claims] In a method for manufacturing a printed film applied to the back of the dial of an indicating instrument in order to equalize the illuminance of the nighttime illumination of the indicating instrument, the unbalance of the illumination is A method for producing a printed film for adjusting night illumination of an indicating instrument, in which negative film that has been photographed as it is is decomposed using a color scanner.