JPS636191B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a recording device that creates an image by applying a recording signal to a recording pen that mechanically scans a recording paper. [Prior Art] Mechanical recording pen scanning recording devices are used for various purposes. For example, in fish finders, ultrasonic pulses are emitted into the water to detect reflected waves from schools of fish, the seabed, etc. A recording pen scans the signal on recording paper in synchronization with the emission of ultrasonic pulses, and also records detected images of schools of fish, the seabed, etc. By doing this, it is possible to detect schools of fish. [Problems to be solved by the invention] In order to determine the type, quantity, bottom sediment, etc. of fish schools from such records, it is desired to record a recording density that corresponds to the signal strength of the reflected wave, but the recording paper At present, the recording characteristics (relationship between recording voltage and recording density) vary, and desired recording characteristics cannot be obtained. In particular, dry recording paper has a problem in that its dead voltage is large and it is extremely difficult to obtain a desired gradation of recording density using conventional means. [Means for Solving the Problems] This invention provides a memory in which recording contents corresponding to the recording characteristics of the recording paper are stored in advance, and reads out the stored contents to generate a gradation recording signal according to the target recording characteristics. Specifically, a grouped address section is provided in the memory, a signal corresponding to the recording characteristics of the recording paper is stored in this section, and the address of this section is recorded. By specifying the signal with the signal obtained by A-D converting the signal and sequentially specifying and reading address parts other than the grouped addresses, the level of the signal to be recorded can be adjusted to the recording characteristics of the recording paper. The above-mentioned problem can be solved by a simple and inexpensive structure in which the replaced signal is given to the recording pen. [Example] Hereinafter, an example will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes an input terminal to which an analog signal to be recorded is applied at a predetermined level. 2 is an A-D converter, and the input analog signal is successively approximated A-D by the clock of the required frequency generation circuit 3.
The conversion converts it into a digital signal. In the figure, 2 bits (4 bits) are used to simplify the explanation.
However, in reality, 8-bit (2 5 6 steps) A-D conversion is performed in one
Possible with IC, 4 bits (8 steps) by experiment
It has been confirmed that smooth changes in recording density are possible with A-D conversion. 4 is a digital signal processing circuit, which is not directly related to the present invention, but has the advantage that interference, noise, etc. can be easily removed by digital signal processing such as a correlation method after A-D conversion if necessary. . Reference numeral 5 denotes an address counter in which lower addresses of the memory 6, that is, addresses A ₀ , A ₁ , and A ₂ are repeatedly designated as addresses for reading out the stored contents by the output clock of the required frequency generating circuit 3. In the example shown, A ₀ to _{A 2} are used for ease of explanation.
Although the lower 3 bits of the output signal are specified, in reality, about 6 bits are required to make fine changes in the output signal waveform. Therefore, the memory 6 is actually an EP ROM or a read-only memory with a capacity of around 1K bits, and in some cases, the memory 6 can be configured such that, for example, four storage contents are output in parallel with one address specification. A readable memory such as 1K bits x 4 words can be used. By storing signal contents corresponding to the recording characteristics of each recording paper, that is, data corresponding to the recording characteristics, in the four storage contents sections, the address specification of the memory 6 can be made common.
It is assumed that four outputs corresponding to each recording characteristic can be obtained, and by switching between these outputs, a recording characteristic corresponding to each recording paper can be obtained. Table 1 is a table showing the relationship between addresses and stored contents in which the addresses of the 32-bit memory are stored in correspondence with the recording characteristics of one recording paper. In Table 1, the storage address part corresponding to the upper bit column is a grouped address part, and is an address that can be seen as one group unit, that is, a group address.

【table】

[Table] Corresponding to each address A ₃ and A ₄ , the storage contents of this part are stored in advance as different data corresponding to the recording characteristics of the recording paper. This memory content corresponds to this part as shown in Table 2 in the case of a recording paper whose recording characteristics are poorer in recording sensitivity in a low voltage region than, for example, the recording paper in Table 1. The stored contents are different in advance, such as having a large number of 1's.

〔Effect of the invention〕

According to this invention, as described above, an analog signal to be recorded is converted into a digital signal of the required bits, and this digital signal is used to read the address of the grouping address part in which the signal corresponding to the recording characteristic of the memory is stored in advance. Since the signal obtained based on the read signal is given to the recording pen by sequentially specifying addresses other than the grouping address part, the desired gradation that matches the recording characteristics of the recording paper can be obtained. It has features such as easy recording, simple configuration, and extremely easy digital signal processing if necessary.

[Brief explanation of the drawing]

The drawings show an embodiment, and FIG. 1 is a block configuration diagram, and FIGS. 2 and 3 are main part signal waveform diagrams. 1...Input terminal, 2...A-D converter, 3...
Required frequency generation circuit, 4... Signal processing circuit, 5...
...Address counter, 6...Memory, 7...
Amplifier, 8...output terminal.

Claims (1)

[Scope of Claims] 1. In a recording device that mechanically scans a recording pen to create an image on recording paper, a. a recording characteristic storage means for pre-recording a signal corresponding to the recording characteristic (hereinafter referred to as recording characteristic signal); b. each address of the group address by a digital signal obtained by A-D converting the signal to be recorded; and (c) readout means for reading out the recording characteristic signal by sequentially specifying each address other than the group address as a readout address, whereby the level of the signal to be recorded can be determined. A recording device characterized in that a signal substituted in accordance with recording characteristics of recording paper is applied to a recording pen.