JPH05104764A - Correction circuit of thermal transfer printer - Google Patents
Correction circuit of thermal transfer printerInfo
- Publication number
- JPH05104764A JPH05104764A JP30099391A JP30099391A JPH05104764A JP H05104764 A JPH05104764 A JP H05104764A JP 30099391 A JP30099391 A JP 30099391A JP 30099391 A JP30099391 A JP 30099391A JP H05104764 A JPH05104764 A JP H05104764A
- Authority
- JP
- Japan
- Prior art keywords
- resistance value
- correction
- correction table
- data
- rom
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Electronic Switches (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は熱転写プリンタに関し、
特にサーマルヘッドの発熱抵抗体の各抵抗値に応じて記
録濃度の変化を補正する補正回路に関する。FIELD OF THE INVENTION The present invention relates to a thermal transfer printer,
In particular, the present invention relates to a correction circuit that corrects a change in recording density according to each resistance value of a heating resistor of a thermal head.
【０００２】[0002]
【従来の技術】一般的に熱転写プリンタにあっては、印
字データに応じてサーマルヘッドの各発熱抵抗体に通電
することでインクリボンのインクを受像紙に転写させて
いるが、サーマルヘッドの各発熱抵抗体の抵抗値にバラ
ツキがあるために、主走査方向で濃度ムラが発生して印
字品質が低下する。2. Description of the Related Art Generally, in a thermal transfer printer, the ink of an ink ribbon is transferred to an image receiving paper by energizing each heating resistor of the thermal head according to print data. Since the resistance value of the heating resistor varies, density unevenness occurs in the main scanning direction and print quality deteriorates.
【０００３】そこで従来から図４に示すように、サーマ
ルヘッドの発熱抵抗体の各抵抗値を格納した抵抗値ＲＯ
Ｍ１０１及び抵抗値に応じて印字データを補正する補正
テーブルＲＯＭ１０２を備え、主走査方向のヘッドアド
レスで抵抗値ＲＯＭ１０１をアクセスして、通電する発
熱抵抗体の抵抗値を読み出し、この抵抗値データと印字
データ（濃度階調データ）とで補正テーブルＲＯＭ１０
２をアクセスして抵抗値に応じて補正した印字データを
読み出すようにした補正回路が知られている。Therefore, conventionally, as shown in FIG. 4, a resistance value RO in which the resistance values of the heating resistors of the thermal head are stored.
A correction table ROM 102 for correcting print data according to M101 and the resistance value is provided, and the resistance value ROM 101 is accessed by the head address in the main scanning direction to read the resistance value of the energized heating resistor, and print the resistance value data. Data (density gradation data) and correction table ROM10
There is known a correction circuit that accesses 2 to read print data corrected according to the resistance value.
【０００４】[0004]
【発明が解決しようとする課題】ところで、例えばサー
マルヘッドとして２０４８ドット（２０４８個の発熱抵
抗体）以上のものを使用する場合、ヘッドアドレスデー
タは１２ビット必要になる。つまり、図５（ａ）〜
（ｃ）にも示すように発熱抵抗体の各抵抗値は個々に異
なり、更に各抵抗値のパターンはサーマルヘッド毎に異
なっている。このように発熱抵抗体の各抵抗値は１つと
して同じものがない場合もあるので、理想的には抵抗値
ＲＯＭの出力も１２ビットで出力できることが望まし
い。By the way, for example, when using 2048 dots (2048 heating resistors) or more as a thermal head, 12 bits of head address data are required. That is, FIG.
As shown in (c), each resistance value of the heating resistor is different, and the pattern of each resistance value is different for each thermal head. As described above, since there is a case where the heating resistors have the same resistance value in some cases, it is ideal that the output of the resistance value ROM can be output in 12 bits.
【０００５】しかしながら、印字データは多階調プリン
タであれば一般的に８ビットであり、これに色信号の２
ビットを加えると、抵抗値ＲＯＭの出力を補正テーブル
ＲＯＭのアドレスデータとして使用できるビット数は６
ビットに制限され、このビット数を増加するには補正テ
ーブルＲＯＭの容量を増やすしかないがコストが高くな
り、現状では４ＭビットＲＯＭを使用しても９ビットが
限界である。However, in the case of a multi-gradation printer, the print data is generally 8 bits, and 2 bits of color signals are added to this.
When adding bits, the number of bits that can use the output of the resistance ROM as the address data of the correction table ROM is 6
The number of bits is limited, and the only way to increase the number of bits is to increase the capacity of the correction table ROM, but the cost becomes high. Currently, even if a 4M bit ROM is used, the limit is 9 bits.
【０００６】そのため従来の補正回路では、各種の抵抗
値のバラツキに対応するために、ある程度広い範囲で補
正するような補正テーブルを用いているが、補正に用い
ることができるビット数は６ビットであるために、補正
テーブルは図６に示すように１本の間隔が広くなって細
かい補正ができない。For this reason, the conventional correction circuit uses a correction table for correcting in a wide range to some extent in order to cope with variations in various resistance values, but the number of bits that can be used for correction is 6 bits. Therefore, in the correction table, one line is widened as shown in FIG. 6, and fine correction cannot be performed.
【０００７】[0007]
【課題を解決するための手段】本発明は上記の課題を解
決するため、補正テーブルの補正曲線の分布を均等にせ
ず、各発熱抵抗体の抵抗値分布に応じて補正曲線の分布
に疎密を与えるようにした。In order to solve the above-mentioned problems, the present invention does not make the distribution of the correction curves of the correction table uniform, but makes the distribution of the correction curves uneven according to the resistance value distribution of each heating resistor. I tried to give it.
【０００８】[0008]
【作用】発熱抵抗体の個々の抵抗値を記憶した抵抗値Ｒ
ＯＭから出力された抵抗値データと記録すべき印字デー
タは、サーマルヘッドの各発熱抵抗体の抵抗値分布に応
じた補正テーブルＲＯＭに入力され、この補正テーブル
ＲＯＭから出力された補正濃度階調データに基づいてサ
ーマルヘッドが駆動される。[Function] A resistance value R storing the individual resistance values of the heating resistor
The resistance value data output from the OM and the print data to be recorded are input to a correction table ROM according to the resistance value distribution of each heating resistor of the thermal head, and the correction density gradation data output from this correction table ROM. The thermal head is driven based on
【０００９】[0009]
【実施例】以下に本発明の実施例を添付図面を参照して
説明する。ここで、図１は本発明を適用した熱転写プリ
ンタの補正回路の要部ブロック図、図２は同補正回路の
各信号のタイミングチャート、図３は同補正回路の補正
テーブルの説明図である。Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is a block diagram of a main part of a correction circuit of a thermal transfer printer to which the present invention is applied, FIG. 2 is a timing chart of each signal of the correction circuit, and FIG. 3 is an explanatory diagram of a correction table of the correction circuit.
【００１０】本発明に係る補正回路は、サーマルヘッド
の各発熱抵抗体の抵抗値を格納し、ヘッドアドレスデー
タでアクセスされる抵抗値ＲＯＭ１と、印字データをラ
ッチしてデータ転送クロックで出力するラッチ回路２
と、抵抗値等に応じた印字データの補正テーブルを格納
し、抵抗値ＲＯＭ１からの抵抗値データ、ラッチ回路２
からの印字データ及び色信号をアドレスデータとしてア
クセスされる補正テーブルＲＯＭ３とを備えており、各
信号の出力タイミングは図２に示すようになる。A correction circuit according to the present invention stores a resistance value of each heating resistor of a thermal head, a resistance value ROM1 accessed by head address data, and a latch for latching print data and outputting it with a data transfer clock. Circuit 2
And a correction table of print data according to the resistance value and the like are stored, and the resistance value data from the resistance value ROM 1 and the latch circuit 2 are stored.
The correction table ROM3 is accessed by using the print data and the color signals as address data, and the output timing of each signal is as shown in FIG.
【００１１】ここで、補正テーブルＲＯＭ３に格納する
補正テーブルについて説明すると、前述したように抵抗
値ＲＯＭ１から出力できるデータのビット数に制限があ
ることから、補正テーブルは抵抗値分布に応じたものと
している。即ち、例えばサーマルヘッドの発熱抵抗体の
各抵抗値分布には、前記したように図５（ａ）〜（ｃ）
に示すような分布があるので、この分布に応じてテーブ
ルを作成する。例えば同図（ａ）に示すような抵抗値分
布であれば、最大補正量が小さいので、抵抗値ＲＯＭ１
はこの範囲で０〜６４（６ビット）フルに抵抗値を示
し、補正テーブルもそれに対応して細かく設定する。The correction table stored in the correction table ROM3 will now be described. Since the number of bits of data that can be output from the resistance value ROM1 is limited as described above, it is assumed that the correction table corresponds to the resistance value distribution. There is. That is, for example, in each resistance value distribution of the heating resistor of the thermal head, as described above, as shown in FIGS.
Since there is a distribution as shown in, a table is created according to this distribution. For example, in the case of the resistance value distribution as shown in FIG. 9A, the maximum correction amount is small, so the resistance value ROM1
Indicates a full resistance value from 0 to 64 (6 bits) in this range, and the correction table is set correspondingly accordingly.
【００１２】また、同図（ｃ）に示すような抵抗値分布
であれば、Ｉ及びIIIの各領域を細かくつまり補正曲線
の密度が濃くなるように設定し、IIの領域は粗く設定す
る。例えば、抵抗値ＲＯＭ１の６ビット（６４本）の
内、Ｉの領域は０〜２５（２６ポイント）、IIの領域は
２６〜３７（９ポイント）、IIIの領域は３８〜６３
（２６ポイント）を割り当てるようにして、これに応じ
て補正テーブルを作成する。この場合の補正テーブルの
例を図３に示している。Further, in the case of the resistance value distribution as shown in FIG. 3C, the regions I and III are set finely, that is, the density of the correction curve is set high, and the region II is set coarsely. For example, among 6 bits (64 lines) of the resistance value ROM1, the area I is 0 to 25 (26 points), the area II is 26 to 37 (9 points), and the area III is 38 to 63.
(26 points) is allocated and a correction table is created accordingly. An example of the correction table in this case is shown in FIG.
【００１３】このように補正テーブルを発熱抵抗体の抵
抗値の分布に応じたものとすることによって、各サーマ
ルヘッド毎に補正テーブルを変更することで、ビット数
が少ない場合でも最大限の補正効果を挙げることができ
る。By thus making the correction table according to the distribution of the resistance value of the heating resistor, the correction table is changed for each thermal head, so that the maximum correction effect can be obtained even when the number of bits is small. Can be mentioned.
【００１４】[0014]
【発明の効果】以上に説明したように本発明によれば、
サーマルヘッドの各発熱抵抗体の抵抗値分布に応じた補
正テーブルを備えたので、抵抗値データのビット数が制
限される場合でも細かい補正ができるようになる。As described above, according to the present invention,
Since the correction table according to the resistance value distribution of each heating resistor of the thermal head is provided, fine correction can be performed even when the number of bits of the resistance value data is limited.
【図１】本発明を適用した熱転写プリンタの補正回路の
要部ブロック図FIG. 1 is a block diagram of a main part of a correction circuit of a thermal transfer printer to which the present invention is applied.
【図２】同補正回路の各信号のタイミングチャートFIG. 2 is a timing chart of each signal of the correction circuit.
【図３】同補正回路の補正テーブルの説明図FIG. 3 is an explanatory diagram of a correction table of the correction circuit.
【図４】従来の補正回路の要部ブロック図FIG. 4 is a block diagram of a main part of a conventional correction circuit.
【図５】サーマルヘッドの発熱抵抗体の抵抗値分布の説
明図FIG. 5 is an explanatory diagram of a resistance value distribution of a heating resistor of a thermal head.
【図６】従来の補正テーブルの説明図FIG. 6 is an explanatory diagram of a conventional correction table.
１…ヘッド抵抗値ＲＯＭ、２…ラッチ回路、３…補正テ
ーブルＲＯＭ。1 ... Head resistance ROM, 2 ... Latch circuit, 3 ... Correction table ROM.
Claims (1)
に応じて印字データを補正するための補正テーブルを備
え、発熱抵抗体の抵抗値に応じて通電エネルギを補正す
るようにした熱転写プリンタの補正回路において、前記
補正テーブルは複数の発熱抵抗体を複数の領域に分け、
最大補正量が大きい領域には補正曲線の本数を少なく、
最大補正量が小さい領域には補正曲線の本数を多く割り
当てたことを特徴とする熱転写プリンタの補正回路。1. A thermal transfer printer having a correction table for correcting print data according to each resistance value of a heating resistor of a thermal head, and correcting energization energy according to the resistance value of the heating resistor. In the correction circuit, the correction table divides a plurality of heating resistors into a plurality of regions,
In the area where the maximum correction amount is large, the number of correction curves is small,
A correction circuit for a thermal transfer printer characterized in that a large number of correction curves are assigned to a region where the maximum correction amount is small.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3300993A JP2635470B2 (en) | 1991-10-21 | 1991-10-21 | Correction circuit for thermal transfer printer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3300993A JP2635470B2 (en) | 1991-10-21 | 1991-10-21 | Correction circuit for thermal transfer printer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05104764A true JPH05104764A (en) | 1993-04-27 |
| JP2635470B2 JP2635470B2 (en) | 1997-07-30 |
Family
ID=17891541
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3300993A Expired - Lifetime JP2635470B2 (en) | 1991-10-21 | 1991-10-21 | Correction circuit for thermal transfer printer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2635470B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0703079A2 (en) * | 1994-09-23 | 1996-03-27 | Hewlett-Packard Company | Reducing energy variations in thermal ink jet printheads |
| US6569589B2 (en) | 2000-07-28 | 2003-05-27 | Canon Kabushiki Kaisha | Toner, toner production process and image forming method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03158256A (en) * | 1989-11-16 | 1991-07-08 | Canon Inc | Image recording device |
-
1991
- 1991-10-21 JP JP3300993A patent/JP2635470B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03158256A (en) * | 1989-11-16 | 1991-07-08 | Canon Inc | Image recording device |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0703079A2 (en) * | 1994-09-23 | 1996-03-27 | Hewlett-Packard Company | Reducing energy variations in thermal ink jet printheads |
| EP0703079A3 (en) * | 1994-09-23 | 1996-05-29 | Hewlett Packard Co | Reducing energy variations in thermal ink jet printheads |
| US6569589B2 (en) | 2000-07-28 | 2003-05-27 | Canon Kabushiki Kaisha | Toner, toner production process and image forming method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2635470B2 (en) | 1997-07-30 |
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