JPH0548458B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a data imprinting device using a liquid crystal.

A data imprinting device for a camera that uses a liquid crystal for displaying data is known, but in the conventional device, there are two segments: a lit segment, that is, a segment to which a voltage is applied, and a non-lit segment, that is, a segment to which no voltage is applied. Due to the low contrast between the two, unlit segments may be imprinted on the film, causing problems such as the data signal not being clearly readable.

In order to eliminate these drawbacks, attempts have been made to improve the polarization degree of the polarizing plate and the rotation performance of the liquid crystal in TN type liquid crystals, but there are limitations and it is not possible to completely eliminate the above drawbacks. Nakatsuta.

The present invention provides a guest-host type liquid crystal that has a segment region whose light transmittance changes depending on whether a voltage is applied or not, an irradiation means that irradiates the liquid crystal with light, and a voltage that changes the transmission state of the segment region. The data imprinting means has a control means for controlling by application, and transmits the irradiation light of the irradiation means through the segment area of the liquid crystal and makes it incident on the film to imprint data, wherein the liquid crystal has a wavelength of at least 400 nm or more.
The transmittance for the 700 nm wavelength light component when no voltage is applied is lower than the transmittance when voltage is applied, and the degree of the decrease is
A blue dye is added which has a characteristic that the wavelength light component of 600 nm to 700 nm becomes larger than that of the wavelength light component of 400 nm to 500 nm, and the irradiation means has a distribution state of the irradiated light component of at least 400 nm. Regarding the wavelength light component of ~700nm,
The relative brightness increases approximately proportionally as the wavelength increases, and the irradiation light from the irradiation means that has passed through the segment area is made to enter from the back side of the photosensitive emulsion side of the film having a red base. By using the base of the film as a filter that cuts out short wavelength light, the contrast can be increased and clear data signals can be imprinted.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the general arrangement of the data imprinting device, in which 1 is a film, 2 is a liquid crystal cell, 4 is an illumination light source, and 3 is a lens that converts light from the light source into parallel light.

When the light source 4 is turned on with the voltage-applied segment of the liquid crystal cell having a high light transmittance and a desired symbol displayed, the light from the light source passes through the lens 3.
The light is converted into parallel light and directed toward the liquid crystal cell, and the light transmitted through the segment reaches the photosensitive emulsion surface from the back side of the film 1, where the displayed data signal is imprinted.

FIG. 2 shows the emission distribution of the illumination light source when a tungsten lamp is used. As shown in the figure, the tungsten lamp is at least
Regarding the wavelength light component of 400 nm to 700 nm, it has wavelength light distribution characteristics such that the brightness increases almost proportionally as the wavelength becomes longer.

Figure 3 is a diagram showing the spectral transmittance of a liquid crystal that has a guest-host effect by adding a blue dye, where A shows the lighting state with voltage applied and B shows the non-lighting state with no voltage applied. . As shown in the figure, the difference between lighting and non-lighting is large on the long wavelength side. When light from a tungsten lamp with the luminous properties shown in Figure 2 is transmitted through such a liquid crystal, the difference in transmitted light between lit segment A and non-lit segment B is more than 600 nm, as shown in Figure 4. It becomes large on the long wavelength side.

When such light enters the red base of a color negative film, the short wavelength light is filtered out by the filter action of the film base, and only the long wavelength light is transmitted through the film base, but the long wavelength light from the non-transparent segments is Very weak, almost only the long wavelength light that has passed through the transmission segment reaches the photoresist film, resulting in a clear imprint.

As described above, the present invention uses a liquid crystal having a guest-host effect to increase the difference in transmittance between a transmitting segment and a non-transmitting segment, thereby making it possible to image a clear data signal with good contrast.

[Brief explanation of the drawing]

Fig. 1 is a layout diagram showing one embodiment of the present invention;
The figure is a diagram showing the emission distribution characteristics of a light source for illumination.
The figure is a diagram showing the spectral transmittance of liquid crystal, and FIG. 4 is a diagram showing the relative brightness distribution of the liquid crystal surface. 1...Light source, 2...Liquid crystal cell, 3...Condenser lens, 4...Light source.

Claims (1)

[Scope of Claims] 1. A guest-host type liquid crystal having a segment region whose light transmittance changes depending on whether a voltage is applied or not, an irradiation means for irradiating the liquid crystal with light, and a method for transmitting light through the segment region. The data imprinting means has a control means for controlling the state by applying a voltage, and the data imprinting means transmits the irradiation light from the irradiation means through the segment area of the liquid crystal and impinges on the film to imprint data, the liquid crystal has a wavelength of at least 400 nm. The transmittance when no voltage is applied for a wavelength light component of ~700 nm is lower than the transmittance when voltage is applied, and the degree of decrease is 400 nm to 500 nm.
Compared to that for the wavelength light component of 600nm~
A blue dye is added that has a property of increasing the 700 nm wavelength light component, and the irradiation means has a distribution state of the irradiation light component of at least
Regarding the wavelength light component of 400 nm to 700 nm, the relative brightness increases approximately proportionally as the wavelength becomes longer, and the irradiation light from the irradiation means that has passed through the segment area is transferred to a film having a red base. 1. A data imprinting device characterized in that the base of the film is used as a filter for cutting short wavelength light by making light enter from the back side of the photosensitive emulsion surface.