JPH11195373A - Light source and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source or a display device to increase brightness generated by optical radiation without increasing an optical radiation amount. SOLUTION: In a light source and a display device, time difference (of -20 ms to -1 ms or +1 ms to +20 ms, favorably) is provided in time base waveforms of light intensity of spectral compositions to mainly stimulate respective pyramidal cells having sensitivity to a long wavelength zone (L-pyramids) and pyramidal cells having sensitivity to a medium wavelength zone (M- pyramids) in human eyes for compensating the time base response difference to light between both cells.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light source and a display device for general illumination.

[0002]

2. Description of the Related Art Various light sources and display devices are currently being developed and used. Fluorescent lamps, which are used in large quantities among artificial light sources, achieve high efficiency and long life by optimizing the design of the phosphors, electrodes, sealing gas, and the like.
Also, based on research on the spectral power distribution of light sources and color reproducibility, various lamps that show colors more vividly have been developed and used.

In recent years, various devices such as CRTs, liquid crystals, and plasma displays have been put into practical use. In these display devices as well, high efficiency and long life are achieved by optimizing the components as in the case of the fluorescent lamp.

[0004] These conventional light sources and display devices have a common point that they emit light when used. The amount of radiation of this light corresponds to the brightness perceived by the light.

When it is desired to increase the amount of light emission in the light source and the display device in order to increase the brightness of the image displayed on the illuminated surface and the display device illuminated by the light source, the light source and the display device are changed to higher output light sources. Or increasing the power supplied to the light source and the display device.

[0006]

In any case, there is no other way to increase the brightness of the illuminated surface or the displayed image except to increase the amount of light radiation itself. Did not.

[0007] It is an object of the present invention to provide a light source or display device that can increase the brightness produced by light radiation without increasing the amount of light radiation.

[0008]

The light source of the present invention is a pyramidal cell (hereinafter referred to as L) having sensitivity to a long wavelength region in the human eye.
Cones) and cone cells having sensitivity in the middle wavelength range (hereinafter M
In order to compensate for the difference in time response to light between the light source and the cone, a time difference is provided in the time waveform of the light intensity of the spectral composition that mainly stimulates each cone cell.

[0009] As light to stimulate the L cone, 550 nm to 6
Light having a main intensity in a wavelength range of 50 nm is used, and light having a main intensity in a range of 460 nm to 550 nm is used as light for stimulating the M cone. The time difference between the light that stimulates the M cone and the light that stimulates the L cone is the time difference between the response of the L cone to light and the response of the M cone to light.

In addition, M for the light that stimulates the L cone
The time difference of the light for stimulating the cone is set to minus 20 ms to minus 1 ms or plus 1 ms to plus 20 ms.

[0011]

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

[0012] The retina of the human eye has photoreceptor cells that receive light and generate nerve signals corresponding to the light intensity. There are roughly two types of photoreceptor cells. One is a cone cell and the other is a rod cell.

[0013] Pyramidal cells are less sensitive than rod cells,
It is most densely distributed in the fovea of the retina corresponding to the center of gaze. In addition, cone cells have three types of cells having different wavelength bands having sensitivity (hereinafter, cone cells having sensitivity in the long wavelength region are L cones, cone cells having sensitivity in the middle wavelength region are M cones, And a cone cell having sensitivity in a short wavelength region is referred to as an S cone). Neural signals from these different types of pyramidal cells are the source of color perception. The evaluation of the illumination light from the light source and the brightness of the display device is mainly performed under light conditions (photopic vision) in which only the cone cells work.

A process in which light from a visual target is received by three types of cone cells in photopic vision and converted into nerve signals corresponding to the brightness of the visual target will be described with reference to FIG. Light incident on the retina is L cone, M cone or S
After the light is received by the cone, the nerve signal output (L) from the L cone and the nerve signal output (M) from the M cone are added, and the nerve signal (L + M) is used as a source of brightness. Is generated.

In this conversion, the neural signal output (S) from the S cone is hardly involved. There is also a conversion of neural signals from the L, M and S cones to neural signals corresponding to chromaticity. There are two types of conversion: a conversion corresponding to a red / green sensation and a conversion corresponding to a yellow / blue sensation.

The red / green sensation is conceptually represented by an operation of (LM + S). A positive result of (L−M + S) indicates a red sensation, and a negative result indicates a green sensation. That is, a neural signal corresponding to the sensation of red for long wavelength light, green for medium wavelength light, and red for short wavelength light is generated. Similarly, the sense of yellow / blue is conceptually represented by an operation (L + MS).

If the result of the calculation of (L + MS) is positive, it indicates a yellow sensation, and if the result is negative, it indicates a blue sensation. That is, a neural signal corresponding to a sense of yellow is generated for long-wavelength light and medium-wavelength light, and a blue signal is generated for short-wavelength light. Similarly, the yellow / blue sense is conceptually (L + M-
S). There is an effect that the brightness can be enhanced by the color sensation generated by these conversions. That is, to enhance brightness and color, the above conversion (L
+ M), (L−M + S) and (L + MS) must be performed efficiently.

Recent studies have shown that there is a time difference between the neural signal transmission of the L cone and the neural signal transmission of the M cone. For example, Stromeyer et al. (Journal of Physiology, Vol. 485, 221-
243 (1995)) that the neural signal of the L-cone is M
We reported that the signal was delayed several milliseconds to several tens of milliseconds from the nerve signal of the cone. That is, even if the stimulation of the L-cone and the stimulation of the M-cone are performed simultaneously by light, the nerve corresponding to the stimulation of the L-cone before the conversion to the nerve signal corresponding to the brightness or the color. The signals differ by a time difference τ.

For this reason, a set of neural signals from the L-cone and neural signals from the M-cone are generated by a conventional light source and display device in which light in all wavelength ranges emits light synchronously. Not a complete set at any of the time points from. For this reason, there is a loss or an error in the addition of the neural signal from the L-cone and the neural signal from the M-cone that generates a neural signal corresponding to brightness or color.

An object of the present invention is to enhance the sensation of brightness and color to light by compensating for a loss or error of a nerve signal caused by a response time difference τ between the L cone and the M cone. I do.

FIG. 1 shows a conceptual diagram of a light waveform emitted from the light source and the display device of the present embodiment. In FIG.
1 is an L-cone stimulating light, and 2 is an M-cone stimulating light.

In FIG. 1, the horizontal axis represents time, and the vertical axis represents intensity. The L-cone stimulation light has a specific time difference τ ′ with respect to the M-cone stimulation light. By doing so, the time difference τ between the neural signal from the L-cone and the neural signal from the M-cone is compensated, and the loss or error of the neural signal when generating the brightness signal in FIG. 1 is reduced. Can be.

The L-cone stimulating light 1 and the M-cone stimulating light 2 can be realized by having a spectral composition corresponding to the sensitivity specific to each cone cell. FIG. 3 shows the difference in spectral sensitivity between the L cone and the M cone. In FIG. 3, the horizontal axis represents the wavelength, and the vertical axis represents the logarithm of the ratio between the spectral sensitivity of the L cone and the spectral sensitivity of the M cone at each wavelength. From FIG. 3, L cone and M
The sensitivity is inverted at 550 nm from the cone.

In order to stimulate only the L-cone, light having a main intensity of 550 nm or more may be used. However, (1) the sensitivity itself to light decreases when the wavelength is too long, and (2) the difference in sensitivity between the L-cone and the M-cone is 650.
Since there is no significant change above nm, the upper limit of the wavelength band having the main intensity is set to 650 nm or less.

In order to stimulate only the M cone, light having a main intensity of 550 nm or less may be used. But,
(1) If the wavelength is too short, the sensitivity itself to light decreases, and (2) the difference in sensitivity between the L cone and the M cone is 460n.
Below m, the lowering of the wavelength band having the main intensity is set to 460 nm or less, since the lowering of the wavelength band decreases.

In FIG. 1, M with respect to L-cone stimulating light 1
The time difference τ ′ of the cone stimulation light 2 is made equal to the time difference τ of the response of the L cone to light with respect to the response of the M cone to light. For example, suppose that τ = 5 ms, that is, the response to light of the L-cone is 5 ms behind the response to light of the M-cone.

In this case, the M-cone stimulating light 2 is compared with the L-cone stimulating light 1 by a time difference τ ′ equal to the time difference τ = 5 ms.
By irradiating with only a delay, the difference in nerve signals existing between the L-cone and the M-cone can be best compensated, and the brightness and color sensation can be enhanced.

The time difference of the neural signal between the L cone and the M cone is described by Stromeyer et al. (Journal of Physiology, Vol. 499, pp. 227-254, 1
997), the time difference τ varies in the range from −20 ms to +20 ms, depending on the experimental conditions such as the spectral composition of the background light. Therefore, strict compensation requires a range from minus 20 milliseconds to plus 20 milliseconds. The time difference plus / minus / zero is no different from existing light sources and displays.

Further, visual information is transmitted from the retinal cells to the cerebrum by the signal density of the nerve impulse signal per unit time. The cell has a rest period of about 1 millisecond from the occurrence of this impulse to the occurrence of the next impulse. Therefore, in correcting the time difference of the nerve signal from the cone, a range from zero to plus or minus 1 millisecond is meaningless. From the above, it is assumed that the time difference τ ′ between the M-cone stimulating light 2 and the L-cone stimulating light 1 is from −20 ms to −1 ms or from +1 ms to +20 ms.

FIG. 4 shows a configuration diagram of the first embodiment of the present invention. In FIG. 4, 41 is a power supply unit, 42 is a delay circuit, 43 is a first light source, 44 is a first illumination light, 45 is a second light source, 46 is a second illumination light, 47 is a visual target, 48
Is a reflected light, and 49 is an observer.

The first light source 43 emits first illumination light 44 having a spectral composition capable of mainly stimulating the L-cone, and is driven by power supplied from the power supply unit 41. The second light source 45 is a light source that emits the second illumination light 45 having a spectral composition capable of mainly stimulating the M cone, and is driven by delaying the power from the power supply unit 41 by the delay circuit 42.

The first illuminating light 44 and the second illuminating light 46 are mixed at the viewing object 47 and are reflected as reflected light 48 by the observer 4.
Nine eyes. In the delay circuit 42, the time difference τ ′ between the first light source 43 and the second light source 45 is set to minus two.
By setting 0 ms to minus 1 ms or plus 1 ms to plus 20 ms, L cone stimulation light 1 and M cone stimulation light 2 as shown in FIG. 1 can be presented, The brightness of the viewing target 47 can be emphasized.

The delay circuit 42 has a configuration for providing a time difference τ ′ for compensating a time difference τ between the response to the light of the M cone and the response to the light of the L cone in the power supplied by the power supply unit 41. This is an element, and may be a phase delay circuit or a phase advance circuit.

Incidentally, for the sake of simplicity, the delay circuit 42
Is provided only between the power supply unit 41 and the second light source 45,
It may be provided between the power supply unit 41 and the first light source 43,
It may be provided between both. Further, the power supply unit 41 is common to the first light source 43 and the second light source 45,
Each light source may be driven by a separate power supply.

For example, the first light source 43 is constituted by a low-pressure sodium lamp, and the second light source 45 is constituted by a high-pressure mercury lamp.
The power can be realized by shifting and supplying the power for driving each of them by the delay circuit 42.

In FIG. 5A, reference numeral 51 denotes the first light source 4.
Lights a1 and 52 from 3 are light a2 from the second light source 45. Let the rising time of the first light a1 be t1, and let the rising time of the second light a2 be t2. The delay circuit 42 compensates the time response difference τ of the cone by setting each rising time to have a difference (t2−t1).

The first light source 43 and the second light source 45
The light emission is not necessarily limited to plasma light emission, and for example, at least one may be light emission obtained by exciting a phosphor with excitation light generated by plasma light emission.

For example, in FIG.
The lights b1 and b4 are referred to as excitation lights b0 and b55 and the second light b2. Here, the second light b2 (55) is converted into the excitation light b0 (5).
It is assumed that light is emitted by the phosphor excited in 4). The rising times of the first light b1 and the excitation light b0 are both t.
1, and the rising time of the second light b2 is t2.

In this case, the time difference (t2-t1) is 4
In the figure, the power supply time difference τ ′ of the delay circuit 42 may be used, or at least a part of the rise time difference may be realized using the time required for the rise of the phosphor emission.

In an extreme case, if there is a time difference of (t2−t1) between the absorption of the excitation light b0 and the emission of the second light b2, even if the setting of the delay circuit 42 is zero, FIG. Has the same effect as described above.

In FIG. 5, reference numeral 56 denotes the first light c1, 57
Is the excitation light c0, and 58 is the second light c2. in this case,
Each of the first light c1 and the second light c2 is light emission obtained by irradiating a different kind of phosphor with the excitation light c0. The rising time of the excitation light c0 is t0, and the first light c1 is
Is a rising time of t1, and a rising time of the second light c2 is t2. The time (t2-t1) corresponds to the delay circuit 42
And may be realized using the difference in the rise time of the phosphor emission with respect to the excitation light c0.

That is, the light is composed of luminescence light having a light emission wavelength of 550 to 650 nm and light having a light emission wavelength of 460 to 550 nm, each of which is time-modulated as the main light emission. A time difference is set in the driving of the two luminescences so as to correspond to a time capable of compensating for a time difference τ of a response of the L-cone to light with respect to the response to the light, or a time difference is calculated using a rise time characteristic of the luminescence. By setting, the light source or display device according to the present invention can be realized. The luminescence may be plasma emission excited by thermoelectrons or a phosphor excited by ultraviolet rays, and the effect of the present invention is not limited by the type of luminescence.

In particular, in the spectral composition of light emission, a phosphor whose main light emission is light having a wavelength of 550 to 650 nm and a phosphor whose main light emission is light having a wavelength of 460 to 550 nm have a time difference between the rising emission characteristics. By using a combination of phosphor materials that compensates for the time response difference τ of the cone stimulated by each light, a light source and a display device according to the present invention can be configured.

As a light source, for example, in a fluorescent lamp device or a fluorescent discharge lamp device, the light source can be realized by a simple and inexpensive manufacturing method of changing the type of phosphor applied to the lamp. A display device such as a CRT display or a plasma display can also be configured by changing the type of phosphor to be applied.

FIG. 6 shows a second embodiment of the present invention intended for a display device which forms a color image by juxtaposing pixels of different emission colors. In FIG. 6, 61 is a display device, and 62 is a part of the display screen. For example, in the case of a color CRT display in which phosphor dots are arranged in a delta, red pixels (R), green pixels (G), and blue pixels (B) are arranged in order, and all are arranged in a triangular shape.

When the arrangement pitch is sufficiently narrowed or the observation distance is increased, juxtaposed color mixture occurs between adjacent pixels, and the same color as that obtained when three colors are mixed is seen. Each pixel is coated with a phosphor that is excited by an electron beam and emits light of a corresponding color light. For the sake of explanation, the main intensity of light emission from the red pixel is 550-65.
0 nm, and the main intensity of light emission from the green pixel is 4
A case in which a red pixel is set ahead of a green pixel in time by setting the wavelength to 60 to 550 nm will be described. With the pixels having such a spectral composition, the light emission from the red pixel mainly stimulates the L cone, and the light emission from the green pixel mainly stimulates the M cone.

The rising characteristic of light emission from the red pixel (R) is shown in the upper right of FIG. The rising time of the emission of the red pixel is assumed to be t1. The rising characteristic of light emission from the green pixel (G) is shown in the lower right of FIG. Let the rise time of the green pixel be t
Let it be 2. The time difference τ ′ = (t2−t1) between the emission of the green pixel with respect to the emission of the red pixel (R) and the time difference τ of the response of the L-cone to the light with respect to the response of the M-cone to τ ′ = By setting such values, the display device with high brightness efficiency of the present invention can be configured.

Although the pixel arrangement is the delta arrangement, it may be an inline arrangement, and the arrangement of the pixels does not affect the effect of the present invention. Further, the shape of the pixel need not be circular, and may be elliptical or striped, and the shape of the pixel does not affect the effect of the present invention.

In the case of a display device in which the phosphor of each pixel is excited and emits light at regular intervals by scanning an electron beam like a CRT display, a phosphor material having a different rise time of light emission with respect to incidence of an excited electron beam is used. Can be realized.

In the case of a display device in which a drive circuit can be provided for each pixel, such as a liquid crystal display having a thin film transistor as a drive circuit on a substrate or a display device in which light emitting diodes are arranged in a matrix, an input signal to a drive circuit for a red pixel is This can be realized by adding a circuit that advances or delays the input signal to the driving circuit for the green pixel.

FIG. 7 shows the spectral composition of each color pixel in an actual CRT display. In FIG. 7, a triangle mark indicates a relative spectral energy of light emission from a red pixel, a circle mark indicates a green pixel, and a square mark indicates light emission from a blue pixel. Since the red pixel emits light in a narrow band having a peak around 630 nm, it can mainly stimulate the L cone.

Although the green pixel has a peak around 530 nm, the main light emission is not necessarily in the range of 460 to 550 nm because the emission band is wide and includes a lot of light of 550 nm or more. Incidentally, when estimated from the spectral sensitivity of the L-cone and the M-cone shown in FIG. 3, in the green pixel having the spectral composition shown in FIG.

Therefore, the main intensity can be obtained by making the emission band of the green pixel narrower than the spectral distribution shown in FIG. 7 or by using a phosphor material that makes the emission peak shorter. Can be concentrated to 460 to 550 nm, and emission that mainly stimulates the M cone can be obtained.

FIG. 8 shows a third embodiment of the present invention intended for a display device for forming a color image by mixing light from images composed of pixels of different emission colors. In FIG. 8, 8
1 is a red image display unit, 82 is a green image display unit, 83 is a blue image display unit, 84 is a first half mirror, and 85 is a second half mirror.
The half mirror 86 emits light from a part of the red image display unit, and 87 emits light from a part of the green image display unit.

As shown in FIG. 8A, the red image display section 8
1 is superimposed on the green image displayed on the green image display unit 82 by the first half mirror 84, and the superimposed image and the blue image displayed on the blue image display unit 83 are converted into a second half image. The images are superimposed by the mirror 85 to form a color image.

The light emission 86 of the red image display portion and the light emission 87 of the green image display portion are light emission at the corresponding image positions. Also, the light emission 86 of the red image display unit
The display devices of the display units 81 and 82 are configured such that the main intensity of the light emission 87 of the green image display unit is 460 to 550 nm and the main intensity of the green image display unit is 550 to 650 nm. For example, when a CRT display is used as a display device, a phosphor whose main light emission is within the above-mentioned wavelength range may be used. When a projection-type liquid crystal display is used as a display device, a spectral component whose main transmitted light is within the above-mentioned wavelength range may be used. A color separation filter having transmission characteristics may be used.

As shown in FIG. 8B, the rising time of the light emission 86 of the red image display portion is t1, and the rising time of the light emission 87 of the green image display portion is t2.

Rise time difference τ '= (t2-t1)
Is set equal to the time difference τ of the response of the L-cone to light relative to the response of the M-cone to light.

To set the time difference τ ′ between the corresponding color images, for example, a time difference τ ′ is provided between a signal for driving the red image display unit 81 and a signal for driving the green image display unit 82. The drive signal timing of at least one of the display units 81 and 82 may be shifted.

When the display units 81 and 82 are display devices using phosphor light emission such as a CRT display or a plasma display, a combination of phosphors is used so that the difference in the rise time of light emission becomes τ ′. realizable.

FIG. 9 shows a fourth embodiment of the present invention for a color display device for controlling pixels having different emission colors at a fixed repetition period (hereinafter, image frame period).

In FIG. 9A, reference numeral 91 denotes a scanning display device. The scanning display device 91 includes at least a red image and a green image. The main intensity of light emission from the red image is in the wavelength range of 550 to 650 nm, and the main intensity of light emission from the green image is in the wavelength range of 460 to 550 nm. Light from the green image can stimulate mainly L cones and mainly M cones.

FIG. 9B shows image frames of a red image and a green image of the scanning display device 91 in chronological order. After writing the first frame on the display screen by scanning,
, And so on.

In the second frame, the image “A” is displayed only on the red image, and nothing is displayed on the green image as in the first frame. In the third frame, the image “A” is displayed on both the red image and the green image. That is, in FIG. 9, the red image precedes the green image by one frame. The number of preceding frames is the time response difference τ of the L-cone with respect to the M-cone.
And an integer N closest to the quotient of the image frame period.

Taking a television as an example, a received video signal is separated into luminance information and color information in order to efficiently transmit color information, and transmitted with different frequency characteristics.
On the receiver side, the display device control signals (R, G, B) are extracted from the video signal by the signal converter as shown in FIG.

In order to give the effect of the display device of the present invention,
As shown in FIG. 10B, between the signal converter and at least one of the R and G display device control signal outputs,
A frame signal delay unit 100 is provided. The frame signal delay unit 100 may be a delay circuit configured by an analog circuit.

FIG. 10C shows the function of the frame signal delay unit 100 when the display device control signal is digital. The frame signal delay unit 100 is composed of a memory, and each address corresponds to a pixel constituting an image of the scanning display device 91. In the frame signal delay unit 100 in FIG. 10C, reading from another address n is performed simultaneously with writing to the position m. Write and read are performed by sequentially changing the address, and the next end of the memory is set as the start end of the memory.

The difference between the read address n and the write address m is the same as the number of image pixels for the N frames. For example, it is necessary to record one byte per data. If one image is composed of 256,000 pixels and N = 2, the memory capacity of the frame signal delay unit 100 is at least 512,000 bytes. is necessary.

The frame signal delay unit 1 thus configured
As a result, R or G can be displayed with a delay of N frames. FIG. 10D illustrates another configuration of the frame signal delay unit 100, taking N = 1 as an example. In FIG. 10D, 101 is a first frame memory, 102 is a second frame memory,
Reference numeral 3 denotes a third frame memory. When writing to the first frame memory 101, reading is performed from the address corresponding to the writing in the third frame memory 103.

When the writing to the first frame memory 101 is completed, the writing to the second frame memory 102 is performed, and at the same time, the reading is performed from the corresponding address in the first frame memory 101. When the writing to the second frame memory 102 is completed, writing to the third frame memory is performed next, and at the same time, reading from the corresponding address in the second frame memory 102 is performed.

When the writing to the third frame memory 103 is completed, this time 10
1 and reading from the third frame memory 103 are performed. By continuing these operations, the image frame can be accurately delayed.

The presentation time difference has been described for the red pixel and the green pixel among the color pixels constituting the color display device. Speaking of the remaining blue images,
It meets the conditions of the spectral composition that stimulates the cone. For example,
Although the blue pixel shown in FIG. 7 has an intensity peak at about 450 nm, it emits light in a wavelength band in which the M cone can be more strongly stimulated as shown in FIG. Although the light emission efficiency is low because the light is emitted in a band that deviates from the standard relative luminous efficiency, it has the property of stimulating not only the S cone but also the M cone more strongly than the L cone.

As described above, by synchronizing a blue pixel with a green pixel and giving a time difference to a red pixel, the effect of the present invention is higher than when only a green pixel and a red pixel are given a time difference.

In the light source, light having a main intensity in the wavelength range of 550 to 650 nm that mainly stimulates the L cone and 460 to 55 that mainly stimulates the M cone are used.
In addition to the light having the main intensity in the wavelength range of 0 nm, the color rendering property is enhanced by being composed of the light having the main emission in the wavelength range of 380 to 460 nm that mainly stimulates the S cone. The wavelength range of 380 to 460 nm or less mainly stimulates the S cone, but from FIG. 3, the M cone can be more strongly stimulated than the L cone.

Thus, as in the case of the blue pixel of the display device, the light source also synchronizes light having a main emission in the wavelength range of 380 to 460 nm with light having a main intensity in the wavelength range of 460 to 550 nm. By doing so, the effect of the present invention is higher than when only the light having the main intensity in the wavelength range of 550 to 650 nm and the light having the main intensity in the wavelength range of 460 to 550 nm have a time difference.

As a lighting device using the light source described above,
For example, there are a fluorescent lighting device and an HID lighting device. The color display device can be applied to, for example, a television receiver using a CRT. In this case, it can be constituted by using phosphors having emission characteristics in narrow bands having different rise times. Further, the present invention can be applied to televisions having different display devices or general displays as long as a presentation time difference can be provided between a red image and an image of another color.

Further, by using the light source or the display device according to the present invention described above, an information display method and a display method with high brightness and color reproduction efficiency can be realized.

For example, an energy saving effect can be provided in an information display device in a car, a display for road control, a display of a store or an entertainment facility, and the like.

[0079]

As is apparent from the above description,
INDUSTRIAL APPLICABILITY The present invention can compensate for the time response difference between human cone cells, maximize the nerve signal corresponding to the brightness and color of light, and have an energy saving effect.

[Brief description of the drawings]

FIG. 1 is a diagram showing waveforms of light having different spectral compositions emitted from a light source or a display device of an embodiment.

FIG. 2 is a schematic diagram of a process of being converted into a neural signal corresponding to the brightness of a visual target.

FIG. 3 is a diagram showing the wavelength dependence of the ratio of L cone sensitivity to M cone sensitivity.

FIG. 4 is a configuration diagram of a light source according to the first embodiment of the present invention.

5A to 5C are diagrams showing waveforms of light having different spectral compositions in the light source according to the present invention.

FIG. 6 is a principle diagram of a display device for forming a color image by juxtaposing pixels of different emission colors according to a second embodiment of the present invention;

FIG. 7 is a diagram showing the spectral composition of each color pixel in an actual CRT display.

FIG. 8 (a) is a configuration diagram of a display device for forming a color image by mixing light from an image composed of pixels of different emission colors according to a third embodiment of the present invention, and (b) an image display unit showing the same operation state. Emission characteristics diagram

FIG. 9A is a schematic diagram of a color display device according to a fourth embodiment of the present invention for controlling pixels having different emission colors at a constant repetition cycle. FIG. 9B is a schematic diagram of a time-series image frame showing the same operation state. Figure

FIGS. 10A to 10D are diagrams showing the arrangement and functions of a frame signal delay unit 100;

[Explanation of symbols]

 1 L cone stimulation light 2 M cone stimulation light

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04N 9/12 H04N 9/12 A

Claims (24)

[Claims] 1. A method for detecting light between a cone cell having sensitivity in a long wavelength region (hereinafter, L cone) and a cone cell having sensitivity in a middle wavelength region (hereinafter, M cone) in a human eye. A light source characterized in that a time difference is provided in a time waveform of a light intensity of a spectral composition that mainly stimulates each cone cell so as to compensate for a time response difference. 2. The light for stimulating the L-cone is 550 nm to 6 nm.
2. The light source according to claim 1, wherein light having a main intensity in a wavelength range of 50 nm is used, and light having a main intensity in a range of 460 nm to 550 nm is used as light for stimulating the M cone. 3. The method according to claim 1, wherein the time difference between the light that stimulates the M cone and the light that stimulates the L cone is equal to the time difference between the response of the L cone to the light and the response of the M cone to the light. The light source according to claim 1. 4. The time difference between the light stimulating the L-cone and the light stimulating the M-cone is from -20 ms to -1 ms or from -1 ms to +20 ms. The light source according to claim 1. 5. A light source comprising a light source having a main light emission of 550 to 650 nm and a light source having a main light emission of 460 to 550 nm mixed with a light which is turned on with a time difference of a phase delay or a phase advance. The light source according to any one of claims 1 to 4. 6. A light emitting device according to claim 6, wherein said light emitting device comprises luminescence light having a light emission wavelength of 550 to 650 nm and light having a light emission wavelength of 460 to 550 nm which are time-modulated as main light emission. A light source characterized in that the light source is set to correspond to a time capable of compensating a time response difference between an L cone and an M cone stimulated by light. 7. A fluorescent lamp device having the light source according to claim 1. 8. A fluorescent discharge lamp device having the light source according to claim 1. 9. A method for detecting light between a cone cell having sensitivity in a long wavelength region (hereinafter, L cone) and a cone cell having sensitivity in a middle wavelength region (hereinafter, M cone) in a human eye. A display device, wherein a time difference is provided in a time waveform of light intensity of a spectral composition that mainly stimulates each cone cell so as to compensate for a time response difference. 10. The light for stimulating the L-cone is 550 nm or more.
Using light having a main intensity in a wavelength range of 650 nm,
The display device according to claim 9, wherein light having a main intensity of 460 nm to 550 nm is used as light for stimulating the cone. 11. The method according to claim 1, wherein the time difference between the light stimulating the L-cone and the light stimulating the M-cone is equal to the time difference between the response of the M-cone to the light and the response of the L-cone to the light. The display device according to claim 9 or 10, wherein 12. The time difference between the light stimulating the L-cone and the light stimulating the M-cone is from -20 ms to -1 ms or from -1 ms to -20.
The display device according to any one of claims 9 to 11, wherein the display period is set to milliseconds. 13. A pixel emitting light having a spectral composition that mainly stimulates the L-cone and a pixel emitting light having a spectral composition that mainly stimulates the M-cone are juxtaposed or mixed to stimulate mainly the L-cone. A display device, wherein a time difference is provided so as to compensate for a time response difference between an L-cone and an M-cone in time modulation of light emission in a pixel and light emission in a pixel mainly stimulating the M cone. 14. An image frame in which pixels having different emission colors are controlled at a constant repetition cycle (hereinafter, referred to as an image frame cycle). An image frame composed of pixels emitting light having a spectral composition that mainly stimulates the cone is stimulated by an integer closest to the quotient of the time response difference of the M cone to the L cone and the image frame period. 14. The display device according to claim 13, wherein an image frame composed of pixels emitting light having a spectral characteristic that stimulates the L-cone is advanced than an image frame composed of pixels emitting light having a spectral characteristic. . 15. A pixel which emits light having a spectral composition which mainly stimulates the L-cone is a red pixel, and a pixel which emits light having a spectral composition which mainly stimulates the M-cone is a green pixel and a blue pixel. 15. The display device according to claim 13, wherein the display device is characterized in that: 16. A light source according to claim 1, wherein light having main light emission in a wavelength range of 380 to 460 nm and light for stimulating the M cone are emitted in synchronization. . 17. A lighting device comprising the light source according to claim 1. 18. A television having the display device according to claim 9. 19. A display monitor comprising the display device according to claim 9. 20. An information display method using the light source according to claim 1. 21. A display method using the light source according to claim 1. 22. An information display method for displaying information using the display device according to any one of claims 9 to 15. 23. A display method for displaying an object to be displayed using the display device according to any one of claims 9 to 15. 24. Light in which a time difference is provided in a time waveform of a light intensity of a spectral composition which mainly stimulates each cone cell so as to compensate for a time response difference to light between the L cone and the M cone. Irradiating light.