JPH0933436A - Optical property estimation method - Google Patents

Abstract

PURPOSE: To estimate space movement in optical response state by irradiating a minute area of a solid sample surface with a beam for excited state, then irradiating a wide area including the minute area before annihilation or attenuation of the excited state, for the next excited state, and then detecting emission at the transition. CONSTITUTION: A minute area, about 5μm in diameter, of the surface of a sample 11 where cyanine dye is dispersed in polymer is irradiated with laser pumping light 14, wavelength about 580nm and pulse width about 6ns, by a light incident mechanism 2 through an optical microscope 2, for excitation. After about 0.5ns continuous excitation, an area, of a diameter about 500μm and including the minute area, is irradiated with excitation light 15 of wavelength about 500nm and pulse width about 6ns, for excitation. The excitation light 14 and 15 are removed from the emission, at the state transition, with an optical filter 4, and amplified by an amplification device 5 and then converted photoelectrically by a photoelectrically converting device 6, and then two-dimensional image is displayed on a display device 7. Thus excited state, or space movement of optical response state of an optical element, is estimated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for evaluating optical properties of optical elements. More specifically, the present invention relates to an optical property evaluation method useful for evaluating the optical properties of highly functional optical elements used in wavelength selective transmission films, reflection films, optical nonlinear effect films, photoelectric conversion devices and the like.

[0002]

2. Description of the Related Art Conventional optical elements used in wavelength selective transmission films, reflection films, optical nonlinear effect films, photoelectric conversion devices, etc. have electrodes inside the elements and use electrical signals for input and output. Since optical information processing of the signal light incident by photoelectric conversion is performed by the photoelectric conversion, there is a drawback that the response speed of the element and the integration density are limited. For this reason,
The progress of optical technology and optoelectronic technology using these conventional optical elements is hindered. Under such circumstances, a highly functional optical element capable of performing optical information processing without photoelectric conversion in the element, that is, a control for controlling and assisting the operation of the incident signal light and the optical element. An optical element capable of performing optical information processing using only light such as light or auxiliary light, and it is desirable to use an optical element capable of performing one optical information processing in one unit element. Was there.

However, in order to actually develop and use this highly functional optical element, the optical properties of the element and the element material are spatially moved in an optical response state such as light emission and light absorption with respect to incident signal light. Needs to be evaluated by detecting as a function of time or spectrum. The optical property evaluation method of the conventional optical element includes a method of evaluating by irradiating a planar element with a single light beam, a method of evaluating by measuring the emission intensity distribution of an optical fiber in the element cross section, the element Evaluation method by detecting a static image of the area that responds to light such as light emission by irradiating the entire surface with ultraviolet light. Furthermore, irradiating white light to the entire element detects non-uniform areas from the static image of absorbed light. However, at present, only the static optical response state of the optical element can be evaluated by any of the methods, and the dynamic optical response state, that is, the spatial movement of the optical response state can be evaluated. Could not be evaluated.

The present invention was devised to solve the above-mentioned drawbacks of the prior art, and provides a new optical property evaluation method capable of evaluating the spatial movement of the optical response state of an optical element. The purpose is to do.

[0005]

In order to solve the above-mentioned problems, the present invention provides a microscopic area in a plane of a solid sample,
Exciting by irradiation with an energy beam to generate a first excited state, and before the first excited state disappears or decays, a region including the minute region and having a wider planar range is irradiated with light. Second higher than
Provided is a method for evaluating an optical property, which is characterized by generating an excited state and detecting light emitted when the second excited state transits to a first excited state or a ground state.

Further, according to the present invention, a minute region in the plane of a solid sample is excited by irradiating an energy beam to generate a first excited state, and the first excited state disappears.
Alternatively, before attenuating, when a region including the minute region and having a wider plane range is irradiated with white light to generate a higher second excited state, the first excited state transitions to the second excited state. Provided is a method for evaluating optical properties, which is characterized by detecting light absorbed by the.

The present invention provides the above method,
One of its modes is to detect emitted or absorbed light by time-resolved spectroscopy by irradiation of pulsed light, or to detect emitted or absorbed light by spectral analysis.
That is, to explain in more detail, in the optical property evaluation method of the present invention, a small area having a diameter of several microns on the surface of a solid sample or in the plane of a thin film sample is irradiated with an energy beam such as light, electron beam, radiation, or X-ray. To generate a first excited state, and before the first excited state disappears or decays and returns to the ground state, a region including a minute region and having a wider plane range than )
When detecting light emission, light irradiation is performed, and when (b) absorbed light is detected, white light irradiation is performed to excite a higher state and generate a second excited state. When the excited state is spatially moved with the passage of time immediately after the excitation during generation of the excited state, not only emission or absorption light in the minute region where the first excited state is generated but also this minute Light emission or absorption light in a region different from the region, that is, a region including this minute region and having a wider plane range than this is detected. In the case where the generated excited state does not spatially move with the lapse of time immediately after the excitation, only light emission or absorbed light in the minute region in which the first excited state is generated is detected. In this way, the spatial movement process of the excited state, that is, the spatial movement process of the optical response state of the optical element is performed by changing the irradiation region range at the time of exciting each state and detecting the emitted light or the absorbed light at the time of state transition. Can be evaluated.

Further, by performing time-resolved spectroscopic analysis by irradiating pulsed light having a pulse width of millisecond or less and femtosecond or more to the light emitted or absorbed at the time of state transition, it is possible to determine the time course of the light response state. The accompanying spatial movement process can be detected as a time-resolved moving image, that is, an image of the optical response state as a continuous still image with time as a function. Furthermore, by spectrally analyzing the emitted or absorbed light at the time of state transition, the spatial movement process with the passage of time of the photo-responsive state is spectrally decomposed into a moving image, that is, the image of the photo-responsive state is made to function as a spectrum. Can be detected as a continuous still image.

[0009]

In the present invention, as described above, the region in which the second excited state is generated is a region including the region in which the first excited state is generated and having a wider plane range than this, and the region at the time of state transition The spatial movement process of the photo-responsive state can be evaluated by detecting the emitted or absorbed light, and the optical response can be evaluated by detecting the emitted or absorbed light by using time-resolved spectroscopy by irradiation of pulsed light. The spatial movement process of the state can be obtained as a time-resolved moving image. Furthermore, the spatial movement process of the photo-responsive state is spectrally decomposed by detecting the emitted or absorbed light by spectral analysis. Can be obtained as a moving image.

As described above, since the spatial movement process of the optical response state of the optical element with respect to the incident signal light can be evaluated, various high-speed and high-density optical information processing of the incident signal light is performed using only light. Highly functional optical elements can be developed and used. For example, an aggregate formed from a single atom or a single molecule is dispersed in the device as a photofunctional aggregate,
It is possible to develop an optical element that uses, as an optical information processing means, the spatial movement process to the other unit light function aggregate in the state of optical response to the incident signal light in each unit light function aggregate. Moreover, the spatial movement process of the optical response state in such an optical element is performed by using one kind of light having the same wavelength as the incident signal light or a different wavelength from the outside of the element,
It can be controlled by irradiating the plane of the optical element from the same angle as the incident signal light, or from a different angle, and the intensity of the signal light required to generate the excited state (optical response state) can also be reduced. That is, by using the optical property evaluation method of the present invention, only the incident signal light and the operation of the optical element, that is, control light or auxiliary light for controlling the spatial movement process of the optical response state is used. It is possible to develop an optical element capable of performing optical information processing by using the optical element. Therefore, the optical response speed of the optical element can be increased and the integration density can be increased.

Further, according to the optical property evaluation method of the present invention, when the agglomerates are dispersed in the device as described above, they are dispersed in a regular array, for example, a three-dimensional lattice array, so that the phase of the incident signal light is The state can be controlled and the information on the phase can be applied to an optical element used for optical information processing. Also, by adjusting the values of the intensity, wavelength, pulse width, phase, etc. of the incident signal light, the excited state in the element, that is, the optical response state is controlled, the arithmetic architecture of the element is changed, and the conventional von Neumann It can be a non-von Neumann type arithmetic architecture rather than a type arithmetic architecture. That is, for one input signal to the logic circuit, the output signal is not uniquely determined by the designed element configuration, but the calculation method is determined by the input signal, and if the input signal is different even for the same element,
Optical elements with different output signals can be developed. It is also possible to develop an optical element in which, when an image having wavelength information and time information is input into the element, the way of responding to an input signal in the element differs depending on the input wavelength band.

[0012]

The present invention will be described below in more detail with reference to examples. Of course, the present invention is not limited by the following examples. (Example 1) 3,3'-dieth which is a cyanine dye
yloxadicarbocyaneine iodid
The optical properties of a thin film sample having a thickness of 30 μm in which e 2 was dispersed in a polymer at a concentration of 0.02 mol were evaluated by detecting the light emitted during the state transition.

FIG. 1 shows an example of the structure of the optical property evaluating apparatus used in this embodiment. Sample (11) is 3,3′-diethyloxadi which is a cyanine dye.
Carbocyane iodide 0.02
It is dispersed in a polymer at a concentration of mol and has a thickness of 30 μm. Wavelength 58 generated by the combination of Q-switched Nd: YAG laser and dye laser
Excitation light (14) with a pulse width of 0 nm and a pulse width of 6 nanoseconds is incident on the optical microscope (1) by the light incidence mechanism (2), and this light is irradiated to a microscopic region of 5 μm in diameter in the plane of the thin film sample (11), This minute region is excited to generate the first excited state. Since the state lifetime of this first excited state is about 2 nanoseconds, the second excited state must be generated within 2 nanoseconds after the excitation. Therefore, after 0.5 nanosecond after excitation, Q
A pumping light (15) having a wavelength of 500 nm and a pulse width of 6 nanoseconds generated by a combination of a switch Nd: YAG laser and a dye laser is incident on an optical microscope (1) by a light incidence mechanism (3), and this light is first A region having a diameter of 500 μm including a minute region having a diameter of 5 μm in which one excited state is generated is irradiated, and this region is excited to generate a second excited state. Then, the light (light emission) emitted when the second excited state transits to the first excited state or the ground state is condensed by the optical microscope (1) through the objective lens (10), and is collected on the optical microscope (1). The installed optical filter (4) removes the excitation light (14) and (15) and efficiently transmits only the emitted light to generate a luminescence image, and the amplification device (5) amplifies the intensity of the luminescence image light. Then, the photoelectric conversion device (6) converts the luminescent image into an electric signal, and
The image is converted into a three-dimensional image and displayed on the display device (7).

Further, the luminescent image transmitted through the optical filter (4) is time-decomposed every about 5 nanoseconds by a gate mechanism attached to the amplifying device (5). That is, the trigger signal is sent to the gate mechanism of the amplifying device (5) with the moment of excitation from the ground state to the first excited state as the origin of time, and the emission image time is extracted by extracting only the emission image every 5 nanoseconds after excitation. An image of decomposition, that is, a luminescence image for each time is observed. This makes it possible to evaluate the concentration of the excited state, the moving speed, and the direction over time. FIG. 2 shows that 5 ns, 10 ns, 15 ns, 20 ns after the first excited state is generated,
The two-dimensional image of the luminescence image time-resolved in 25 nanoseconds is shown, (21) is the luminescence image after 5 nanoseconds, (22)
Is an emission image after 10 nanoseconds, (23) is an emission image after 15 nanoseconds, (24) is an emission image after 20 nanoseconds, and (25) is 2
It is an emission image after 5 nanoseconds. From FIG. 2, it can be seen that the luminescent image spreads on the concentric circles over time. This indicates that the cyanine dye is isotropically dispersed in the polymer of the sample. Further, a part of the luminescence image is distorted because of the influence of impurities such as dust in the sample, or at a portion where the cyanine dye is dispersed unevenly.

In the case of time-resolving at shorter intervals, the incident photons are photoelectrically converted, and then the incident electron beam is deflected by a high-speed electric field swept at high speed to convert the time axis into a space axis. Time adjustment device (8)
Can be time-resolved to the order of picoseconds by installing between the amplification device (5) and the photoelectric conversion device (6) as required, and thus a more detailed spatial movement of the excited state can be evaluated. It can be carried out.

(Example 2) 3,3 'which is a cyanine dye
-Diethyloxadic bocyanine
The optical properties of a thin film sample having a thickness of 30 μm in which iodide was dispersed in a polymer at a concentration of 0.02 mol were evaluated by detecting the light absorbed during the state transition.

In the apparatus of FIG. 1, Q switch Nd: Y
Excitation light with a wavelength of 580 nm and a pulse width of 6 nanoseconds generated by the combination of an AG laser and a dye laser (1
4) is made incident on the optical microscope (1) by the light incident mechanism (2), and this light is irradiated to a minute region having a diameter of 5 μm in the plane of the thin film sample (11), and this minute region is excited to produce the first excited state. Is generated. 0.5 nanoseconds after the first excitation, white light is irradiated by the white light incident mechanism (9) to a region of 500 μm in diameter including a minute region of 5 μm in diameter where the first excited state is generated, and the region is excited. To generate the second excited state. The white light is white light generated by irradiating water contained in a quartz cell with continuous white light emitted from a mercury lamp, a xenon lamp, a halogen lamp, or a laser having a pulse width of about picoseconds. Light pulses can be used. Then, the light absorbed when the excited state is generated is condensed by the optical microscope (1) through the objective lens (10), and the excitation light (is generated by the optical filter (4) installed on the optical microscope (1). 14)
(9) is deleted and only the absorbed light is efficiently transmitted to generate an absorbed light image, and the absorbed light image is amplified in intensity by the amplifying device (5), and then by the photoelectric conversion device (6). It is converted into an electric signal and displayed on the display device (7).

The time resolution of this absorbed light image is time resolved about every 5 nanoseconds by the gate mechanism attached to the amplifying device (5), like the time resolution of the emission image in the first embodiment. Furthermore, a time resolution device (8) similar to that of the first embodiment.
Is installed between the amplifier device (5) and the photoelectric conversion device (6), it is possible to perform time resolution in picoseconds.
Thus, the time-resolved image of the absorbed light allows observation of the absorption image for each time, and thus the concentration of the excited state, the moving speed, and the direction can be evaluated.

(Embodiment 3) FIG. 3 shows an example of the structure of an optical property evaluation apparatus for irradiating a sample with excitation light using an optical fiber. The tip of the quartz optical fiber is processed to have a radius of curvature of several nm to several tens of nm, and a quartz optical fiber probe (12) with a metal coating for light shielding is installed on the back surface of the sample (11) to provide an excitation probe light source. (13)
The excitation probe light is irradiated onto the sample (11) through the quartz optical fiber probe (12). With this quartz optical fiber probe (12), the irradiation area in the plane of the sample has a diameter of several tens.
Since it can be set to a minimum region of about nm, a more detailed photoresponse state can be evaluated.

[0020]

As described in detail above, according to the present invention, the region where the second excited state is generated is a region including the region where the first excited state is generated and having a wider plane range, and the state transition is performed. The spatial movement of the excited state, that is, the optical response state of the optical element can be evaluated by detecting the emitted light or the absorbed light at the time. Furthermore, by detecting the emitted or absorbed light by using time-resolved spectroscopy by irradiating pulsed light, the spatial movement of the photo-responsive state can be obtained as a time-resolved moving image. Since the spatial movement of the photo-responsive state can be obtained as a moving image of the spectrum decomposition by detecting the photo-responsive state by performing spectrum analysis, the optical properties such as the density, moving speed and direction of the photo-responsive state of the optical element are evaluated. be able to.

As described above, since the spatial movement process of the optical response state of the optical element with respect to the incident signal light can be evaluated, the operation of the incident signal light and the optical element, that is, the spatial movement process of the optical response state is controlled. It is also possible to develop an optical element that can perform optical information processing using only light such as control light or auxiliary light for assisting, thus increasing the optical response speed of the optical element and increasing the integration density. It can be densified.

[Brief description of drawings]

FIG. 1 is a configuration showing one structural example of an optical property evaluation apparatus.

FIG. 2 is a diagram showing a time-resolved luminescence image of a thin film sample detected in Example 1.

FIG. 3 is a configuration diagram showing a structural example of an optical property evaluation apparatus that irradiates a sample with excitation light using an optical fiber.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical microscope 2 Light incidence mechanism 3 Light incidence mechanism 4 Optical filter 5 Amplification device 6 Photoelectric conversion device 7 Display device 8 Time resolution device 9 White light incidence device 10 Objective lens 11 Thin film sample 12 Quartz optical fiber probe 13 Excitation probe light source 14 Excitation light source 15 Excitation light source

Claims (5)

[Claims] 1. A microscopic region in a plane of a solid sample is excited by irradiating with an energy beam to generate a first excited state, and the microscopic region is included before the first excited state disappears or decays. , A higher second excited state is generated by irradiating a region having a wider plane range than this, and light emitted when the second excited state transits to the first excited state or the ground state is detected. An optical property evaluation method characterized by the above. 2. A micro region within a plane of a solid is excited by irradiating an energy beam to generate a first excited state, and the micro region is included before the first excited state disappears or is attenuated. It is characterized in that a higher second excited state is generated by irradiating a region having a wider plane range with white light, and light absorbed when transitioning from the first excited state to the second excited state is detected. Optical property evaluation method. 3. The optical property evaluation method according to claim 1, wherein light emission or light absorption is spatially detected. 4. The optical property evaluation method according to claim 1, wherein the emitted or absorbed light is detected by using time-resolved spectroscopy by irradiation with pulsed light. 5. The optical property evaluation method according to claim 1, wherein the emitted light or the absorbed light is detected by spectral analysis.